Tag Archives: A to B 39

A to B 39 – School Run – Dare to be Different!

atob39-coverOur advocacy of electric bikes continues to cause controversy. Some readers have made the point that they never see electric bikes on the road, so why bother testing them? Had ‘A to B’ been around in 1903, we would certainly be trying the new steam and petroleum-powered automobiles. They’d be slow, unreliable and offer a limited range. No doubt we’d get letters telling us that they were elitist, expensive, never likely to replace the horse, etc, etc.

The petroleum automobile went on to be rather too successful, which is partly why we’re looking at alternative means of locomotion in 2003. It’s always hard to judge the future of transport, but we’re bound to see massive change in the next few years, and we’re convinced that electric bikes will have a serious role to play when the dust settles.

We may look back in a decade or so and laugh about the 8mph pedicabs with a range of 19 miles, but we will also be glad that we experimented with – and in a small way, helped to perfect – such pioneering machines. That’s why we will continue to feature electric bikes.

A to B 39 Contents

A to B 39 Blog, Cycling Statistics, Peak Oil

FIRST PUBLISHED December 2003
Dubious Cycling Statistics, Peak Oil
David Henshaw

A plain brown envelope arrived recently at Mole Towers containing a fascinating publication entitled A2B. A vaguely familiar name to readers of this organ no doubt, particularly when we consider that the title in question is bi-monthly and, broadly-speaking, concerned with transport?

A2B is an internal publication from our old friends at the Department for (Road) Transport. Despite the accent being largely (although not exclusively) on road matters, A2B is a perfectly readable in-house journal, but one wonders whether it might not bear just a little too much similarity to A to B? It seems some DfT staff did voice concerns, but their Communications Directorate carried on regardless.

Somehow, one doubts whether A to B has many friends in the Department. Back in A to B 30, a graph appeared in this very column indicating that – on the DfT’s own statistics – cycle usage in the UK appeared to be in a state of terminal decline, while car usage was growing at a healthy rate. Thereafter, the cycling figures mysteriously disappeared from DfT bulletins, leaving us rather in the dark as to trends.

Why worry? Well, rather a lot depends on such figures, notably the local and national funding of cycle facilities for organisations such as the very admirable Sustrans. After all, who in their right mind would pour money into a mode of transport that was apparently doomed? On the other hand, an increase in cycle use helps to unlock funds for cycle facilities and restrict spending on motor cars. ‘Green’ transport look very good at election time too, so accurate figures are important. But once those pesky politicians get involved, there’s often pressure to ‘mould’ the figures to give the desired results.

In the summer of 2003, the DfT cycle figures quietly returned, this time indicating a steady growth in cycle usage rather than the previous marked decline. The discrepancy, we were told, was due to the way the figures had been gathered, as traffic surveys had previously looked only at major roads.

Now, hold on a minute. If every survey since 1993 has failed to spot millions of cyclists, how have the statistics been so precisely revised? Do they now include Sustran’s own – much more optimistic – figures, recorded largely on leisure paths?

Far be it from the Mole to doubt the honesty and integrity of a government department, but one cannot help but wonder whether someone, somewhere might not have been a little economical with the actualité? Either the original figures are correct (suggesting that cyclists are being driven off the roads in big numbers), or cycle use really has been growing steadily for the last decade, but the mandarins at the DfT have been keeping us in the dark.

On the other hand, far from being a conspiracy, the affair might just be a clumsy attempt to bury yet another world-class cock-up. Forget the cycling statistics; the real problem is the steady growth in motorised road transport.A glance at the graph reveals that although car use was checked briefly by the fuel ‘crisis’ of 2000 and the early days of our rather dubious invasion of Iraq, vehicle mileage rapidly caught up the lost ground, growing by more than 2% in the last three months alone.

A to B magazine, Cycling Statistics
As readers of A to B will be aware, fuel cell technology remains in its infancy, but the experts are suggesting that global oil supply is likely to be overtaken by demand within ten years. If one had a barrel of oil for every occasion this had been predicted in the last century, one would, of course, have some significant reserves, but this time the experts appear to be rattled.

Predicting such things is a notoriously inexact science, but the forecasts suggest that an apparently insignificant reversal in the supply/demand equation will cause panic buying and a sharp upsurge in prices, although quite when and to what extent, no one knows.

The nations that will suffer most are those that (a) have used up their own hydrocarbon reserves, (b) concentrated inland transport in oil-hungry aircraft and road vehicles, and (c) declared war on the countries with all the remaining oil reserves. Er, sounds familiar… Some say the crunch could arrive within twelve months.

Speaking of global catastrophes, one is drawn, as if by some invisible force, to the railways, where track maintenance is ‘being brought back in-house’, as Network Rail would have it, but take no notice – this is re-nationalisation. We already have the infrastructure back in state hands, with maintenance going the same way.

According to an internal review: ‘…a single integrated rail maintenance operation’ would deliver higher standards, ‘significant efficiency savings’ and improved safety. Surely British Rail delivered just such benefits before it was dismantled? National ownership ONE, Private ownership NIL, and not a moment too soon. At Bogworthy Junction, a once proud outpost of the Great Western Railway (once privately-owned, then private with state-characteristics, state owned, quasi- private, etc, etc), the nightmare complexity of railway privatisation has resulted in all but one of the staff packing their bags.

On top of the sort of duties one would expect to see in the job description: issuing tickets, waving flags at trains, helping customers over the bridge, cleaning the toilets, sweeping the platforms, dealing with complaints against his employer (and 25 others), staff are expected to provide fax and phone facilities, toilets and a regular brew up for an assortment of gorillas in orange jackets working for contractors, sub-contractors, and any other outfit that might choose to send gorillas to this remote outpost. No one seems to know or care who they are these days.

Incidentally, a rough calculation reveals that Bogworthy may have a turnover of £3 million a year. One wonders how many people would be willing to run such a business single-handedly for wages of a little over £5 an hour? Yes, £11,000 a year. Shouldn’t the DfT be involved?

Electric Bike Range Claims

“I would like to query the basis of the electric bike range statistics you quote. I realise that you are ‘A to B’, but for many people, their use of such a bike for leisure purposes would be ‘A to A’; that is to say starting and finishing at the same location. If one assumes a hilly terrain, and ignores any flat areas, at the completion of a journey the uphill sections will have equalled the downhill. If therefore, one only used the electric-assist on the uphill sections, and turned the motor off on the downhill sections to freewheel, would the ranges you quote notionally be doubled?”

Michael Bartlett, Shoreham-by-Sea

Unfortunately, life is rarely that simple. For one thing, where a bike has the capability, the A to B testers usually opt for speed over range, which is why tests always quote the average speed.To keep speed up, the motor is often used for long periods on the flat, as well as climbing hills. Secondly, you never get back all the energy expended climbing a hill going down the other side! This is partly because motors tend to be inefficient when climbing at low speed, but primarily because most of the energy is dissipated in fighting the wind.This effect is barely noticeable at low speed, but descending a hill at 30mph will scrub off much of the kinetic energy stored on the climb…This is why ‘regenerative’ braking (recharging a battery or other storage device on a descent) is hardly worthwhile on a bicycle.

Think of the hill as a battery:Whether you ride a conventional or power-assisted bicycle, you store kinetic energy on the way up, and discharge it on the way down. A heavy freight train crossing the Swiss Alps will store a great deal of energy, which can usefully be returned to the electricity grid going down the other side, but a bicycle stores a tiny amount, and on such a small lightweight vehicle, wind resistance has a comparatively large effect. On a switchback road, the stored energy may enable you to get half way up the other side, so it can be useful, but in most cases, mechanical or electrical storage devices would be of little help. Now, where were we?

The A to B 17.6 mile test route starts and finishes at about the same elevation, but climbs and falls almost continuously in between, so the motor tends to be used for a high proportion of the ride.The figures published in the magazine are always lower than the maximum achievable, although they seem to equate fairly well to the sort of range a typical rider might expect, making shorter trips in heavier stop-start traffic.

In terms of maximum range, in level country, you might expect to exceed the A to B figures by 40% or more, even when using the motor much of the time. For example, the Powabyke or Ezee Forza can manage 50 miles relatively easily on the flat.

Most bikes complete the test course in 75-80 minutes, but the Forza did the run in 62 minutes – exactly 17mph. How can a bicycle limited to 15mph maintain such a high speed? The reason is that the more powerful machines cruise at close to 15mph and rarely fall below 10mph on hills.Add a few downhill bursts, and the average speed can exceed the maximum assisted speed…This is why electric bikes work so well in hilly areas.

Greenspeed GT3

greenspeed-gt3-recumbent-trikeRecumbent bikes and trikes are cumbersome things, which helps to explain why they remain relatively unpopular for day-to-day use, although for recreation and sheer entertainment, laid-back cycling is unbeatable.

There are a handful of practical folding recumbent bicycles around, notably Bike Friday’s ever-so-clever 16-inch Sat-R-Day, but trikes are trickier to transport. For car-top recreational use, that’s hardly an issue, but we don’t go there, so you’ll have to read about such things elsewhere. For preference we try to choose machines that can be carried by train or plane, or tucked in a bike trailer, that sort of thing.The only recumbent trike that passed the A to B criteria was Nick Abercrombie Andrew’s GNAT folder (see A to B 8), albeit at the expense of considerable cost and complexity.

Greenspeed is an Australian manufacturer, and one of those companies you think you know all about, but discover you knew very little. It all began back in 1990, when Ian Sims, an ICI laboratory technician, lost his job. Ian had been involved in the motor racing world, designing and building his own mid-engined sportscar and a number of electric racing machines, but with time on his hands, he began to investigate more relaxed transport, and his mind strayed towards the alternatives.

This process was given a vital extra impetus when Ian lost his licence (‘94 clicks in a 60 zone!’). After dissecting and dismissing his sons’ mountain bikes, the race-orientated mind began to think along more wind-cheating lines.The final piece in the jigsaw followed a ride on an early Trice recumbent trike, which brought Ian to the time-honoured conclusion that he could do better. Later in the year, with a prototype under his arm, Ian entered the 540km Great Victoria Bike Ride, and – although rider and machine were largely untested – he found himself completing the 80km daily stages by lunch-time and waiting for the more conventional ‘safety’ bicycles to arrive.

greenspeed-gt3-recumbent-trike-2

In recumbent trike terms the GT3 has a fairly upright seat back, but the small wheels help to create a low profile machine.

The first production machine was sold to a New Zealander who had been on that original ride, and the business slowly grew.Within five years Greenspeed had moved from a family workshop to a factory unit ‘five minutes down the cyclepath’. In another five years, the company had absorbed the two adjacent factory units and was churning out 250 trikes a year. Of the 1,400 built to date, more than 80% have been exported (mainly to the United States) generating foreign exchange of $1.6 million AUD, of which the company is justifiably proud. Ian is much too polite, so on his behalf, we’ll blow a long overdue raspberry at ICI.

The Theory

For some years, Greenspeed has concentrated on smallish 406mm (20- inch) wheeled machines, but there has been a gradual move towards the ‘Brompton’ 349mm (16-inch) format, and the GT3 is the latest of these.The big advance is the incorporation of a hinge in the mainframe, and construction in Taiwan, resulting in a budget price (in recumbent trike terms) of about £1,900.

Small wheels are useful on bicycles, but overwhelmingly beneficial on recumbent trikes: the wheels are stronger and lighter, offering faster acceleration and reduced wind resistance.They also exert a lower twisting force on the frame when cornering, so the frame can be made simpler and lighter, and they reduce the length and the height of the machine, cutting wind resistance still further. And with the rider sitting closer to the ground, a slightly more upright seat can be fitted, improving comfort and visibility.

…if you haven’t ridden a recumbent trike, you’ve missed out on one of life’s Great Experiences…

Rolling resistance is a little higher with 349mm tyres, but the GT3 comes with Primos – still arguably the free-est rolling and lightest 349mm tyres on the market. In any event, the higher rolling resistance is almost certainly outweighed by the benefits.True, the small wheels can ride a bit harshly on poor roads, but as we shall see, this can be improved.

Recumbents are produced with a variety of seat angles, from laid back versions of a conventional bike to a near full recline, which gives the least wind resistance but puts a nasty crick in your neck. In recumbent terms, the GT3 has a relatively conservative 40 degrees seat back – a reasonable compromise between visibility and a low frontal area.

The Practice

Once the boom length has been set and you’ve levered your feet into the toe- strapped pedals, you’re away. Like all the best trikes, the GT3 has lots and lots of gears, fingertip control, and a transmission that translates every ounce of effort into forward motion.

greenspeed-gt3-recumbent-trike-3If you haven’t ridden a well-sorted recumbent trike, you’ve missed out on one of life’s Great Experiences. And by any standards, this well-balanced and agile, yet forgiving, machine is an experience you’re unlikely to forget in a hurry. Like all the best mid-engined sports cars, geometry and weight distribution have been chosen to give handling that’s broadly neutral – in other words, should you over-cook things on a sharp bend, the GT3 will neither plough straight on, or head for the apex.We rode the trike in all sorts of conditions, with a variety of tyre pressures and several drivers, and the thing cornered throughout as though on rails.This seems to hold true on dry surfaces, wet surfaces and – a Somerset speciality – manure-covered surfaces.You need to concentrate, because things happen very quickly when you’re sitting on the ground, but we’d guess that’s part of the fun with a mid-engined sports car too.With a bit of familiarity, you soon find yourself cruising through corners that would send a cyclist sliding into the hedge. Once in a while, the front Primo tyres scrabble for grip, and occasionally the rear end ducks and dives on a bump, but at bicycle speeds, there’s plenty in reserve.

Unlike an upright bicycle, it isn’t really possible to absorb bumps using your legs and body. Initially, we inflated the Primo tyres to their maximum pressure of 85psi, which worked well enough at the front, but the jarring and vibration from the back wheel was enough to give blurred vision on indifferent surfaces (they’re the only kind in these parts). After a bit of fiddling, we settled on 40psi at the rear, which improved the comfort level immensely, and had no obvious effect on performance.The front tyres seemed less critical, presumably because vibration from the front passes through a squidgy bottom rather than a relatively bony upper back.

In all the excitement (yes, every ride is exciting), you tend not to notice that you’ve become plastered in the water, mud and bovine waste material that made it all so entertaining.The GT3 has a substantial rear mudguard and mudflap, but there’s no protection at the front. Normally, spray from the front wheels shoots clear in two muddy arcs, but occasional changes of direction or errant wind eddies send a chocolatey spray across your arms, chest and face.There’s not much you can do about this, except emigrate somewhere drier or reckon on taking a hot shower after every ride.

Progress on the GT3 is exceedingly rapid, and even when it isn’t, it appears to be, which is what getting from A to B is all about. Our test hill revealed an average speed of 15.4mph – much faster than a 16-inch wheeled bicycle, indeed broadly similar to a full-size racing bike. On steep descents, speed rises rapidly, and when you’re this close to the ground, 20mph seems fast, and 30mph becomes sound-barrier stuff.

Brakes

Steering a 68cm-high projectile down country lanes is all very well, but sooner or later you’ll need to apply the brakes.The GT3 has no rear brake, so the legal requirement for two independent systems is taken care of with separate Sturmey Archer front drums and levers.This not only gets around the brake balance problem (see KMX trike, A to B 37), but enables the rider to make hand gestures whilst braking in a smooth and controlled manner with the other hand.

The magic ingredient is some carefully chosen geometry, including ‘centre-point’ steering that puts the tyre/road contact patch immediately under an inclined steering pivot. Should you apply one of the two front brakes, there’s very little tendency for the bike to swivel around the contact patch, so it stops in a straight line.

On the GT3 you can make quite harsh stops with one brake and feel barely a twitch in the steering. A panic stop locks the wheel at 0.3G, but the trike still pulls up more or less straight (or in a curve, if you happen to be cornering). Peak performance, using both brakes, is around 0.6G, and those with strong hands can hit 0.65G, at which point the rear wheel begins to lift off. Either way, the stop is nicely controlled and drama-free.

To get the best from the brakes, you have to juggle the levers for perfect balance, but the GT3 provides plenty of feedback, particularly at higher speed. Within a few miles, your body learns to react to the subtle messages from the wheels, but even if you get it wrong, the trike is essentially fail-safe.

Gears

greenspeed-gt3-recumbent-trike gearsHill climbing is a bit disappointing, not because the GT3 climbs particularly slowly, but because the climbs are markedly slower than the descents. Actually, the trike maintains a good pace on the sort of mild nagging gradients that might depress a bicyclist, but on steeper climbs, the bicycle is quicker, leaving the trike rider to sit it out and think about the fun they’ll have going down the other side.

Thanks to their relatively poor hill-climbing and slick descents, recumbent trikes usually come with enormous gear ranges, with Greenspeed typically providing three separate stages, and as many as 72 gears. On the 16-inch wheeled GT3, there just isn’t the space, so the machine is fitted with the new Shimano Capreo derailleur, specifically designed for small-wheelers.This nine-speed gear cluster, coupled to Shimano Tiagra triple chainrings, gives a near 500% range, and 27 gears in three groups: 20″- 57″, 27″- 79″ and 34″- 98″. Not quite low enough for serious climbs, or high enough for spinning down long fast descents, but a fair compromise.The Capreo gear cluster is unusual – the six largest sprockets slide onto a conventional freewheel hub, with the 11, 10 and 9-tooth tiddlers individually mounted on a smaller splined shaft.This will no doubt prove useful, because you can bet the small ones will wear out fairly quickly and cost a fortune to replace.With such tiny sprockets, the chain tends to oscillate in speed as each tooth passes, which can be felt as a soft (but by no means annoying) vibration in the highest gears.

It’s hard to judge how efficient the Capreo is, but it provides a good range of gears, and helps to keep the chainrings down to a manageable size, even on a 16-inch bike.

A to B Things

greenspeed-gt3-recumbent-trike-5

The GT3 puts a new slant on the school run. Panniers have little effect on handling, but 20kg above the rack does!

The GT3 makes an excellent platform for the school run – a bit unconventional, but you’ll get home before the other parents have walked their children to the car. Generally, a child seat is mounted above a 26″ wheel, putting the child behind and slightly below the rider. On the GT3, the seat mounts atop a smaller 16-inch wheel (albeit on a 20-inch rack, so not quite as low as it might be), but you’re sitting lower still, giving the child a grandstand view over your head. Perching 20kg above the rear wheel is a bit like strapping a rhinoceros to the back of a sport car. On corners, the GT3 betrays a definite nervousness as the child seat gently twists the rack and frame, but it still runs true as a die, at the usual rocket-like speeds in a straight line.

Panniers, of course, are mounted much lower, so this pendulum effect should be minimised. Any of the shorter jobbies suitable for 20-inch bikes will fit, and there’s plenty of clearance. The rack has a bracket for a standard LED rear light, and the frame features braze-ons for a dynamo (not a great idea with frail Primo tyre sidewalls), a front light and a bottle cage.There’s also a mirror, mounted on the kingpin in classic trike style, but the stem is really too short to provide much information.

Obviously, light touring is well within the GT3’s capabilities, but with ground clearance of only 7cm, you’d be well advised to stick to the black top. On a more practical note, the turning circle of 3.3 metres (10′ 9″) is one of the best around, making U-turns and other dubious manoeuvres dead easy.This may not look like a shopping or nip-to-work machine, but provided you’re willing to mingle with traffic at wheel-nut height and you keep clear of road humps, all the practical elements are there.

Folding

greenspeed-gt3-recumbent-trike-folded

When folded, the rear wheel settles to the left of the boom.

Almost forgot. Folding involves removing the single seat bolt with a 6mm allen key, which exposes the hinge in the main frame tube, or ‘spine’ in recumbent-terminology. The hinge is a nice bit of engineering, superficially similar to the Zero hinge (see page 35), but neater and lighter, with an even craftier safety catch. Like the Zero, the quick-release pivot shaft forms the catch, engaging through a hole on the front hinge face. But in this case, a peg on the shaft engages with a cam cut in the hinge body, so the catch will only disengage when the quick-release is rotated down and back.

greenspeed-gt3-recumbent-trike-frame-hinge

Note the frame hinge

Like the Bike Friday, the hinge is asymmetrical, so the rear frame swings up and to the left, allowing the rear wheel and rack (if fitted) to nestle snugly between the left front wheel and the boom.The lengthy chain pivots at around the same point, so it stays in tension.With the seat strapped to the right of the fully retracted boom (another 6mm allen key job), the trike measures 82cm wide x 52cm tall x 101cm long.

In bicycle terms, a folded volume of 430 litres (15 cubic feet) would be vast, but for a trike it’s really quite compact. And the folding process takes only a minute or two.This sort of performance brings the GT3 into train territory, provided you keep a low profile and are very nice to the guard if spotted (technically, trikes are not allowed on trains).We’d strongly recommend putting it in a bag, both for protection and disguise. A typical hatchback car would be easy, although squeezing the GT3 into a car boot might require a little more work.

…enough performance to satisfy the hot-blooded young things…

If you’re prepared to get into the oily dismantling zone, there are plenty of other options to make the machine quite a bit smaller. Remove the wheels (a single allen screw for each front wheel), steering assembly (one bolt, again), derailleur and chain (more fiddly) and boom, and in about 30 minutes, the bits can be squeezed into a case measuring 38cm x 71cm x 77cm. We can vouch for that, because that’s how our trike arrived, hot from its launch at the Interbike trade show in Las Vegas.Yes, it’s big by train or plane standards, but a transport trike nonetheless.

Conclusion

With most of these machines being unashamedly roof-of-the-car jobs, the GT3 has very little competition. A bit disappointing that the ultimate HPV has to be carried everywhere by car, but there you are. Green transport, eh?

The traditional trike manufacturers seem to have become a bit set in their ways, selling increasingly expensive machines to wealthy and slightly paunchy middle-aged men with beards. For what it’s worth, a typical Windcheetah,Trice or Greenspeed (pricing is difficult because recumbents are virtually bespoke) costs £2,400 to £3,000.That’s a great deal of dosh for most of us.

Against this background, the ‘entry level’ GT3 is a nice, simple practical package, selling for £1,900 or so. No super-duper components, but enough performance to satisfy all the hot-blooded young things who tried it, and leave some of them making lost puppy noises. Quite how many of these un-bearded types with a mortgage and two kids would be allowed to part with two grand is another matter, but there’s no doubt that the GT3 represents a breakthrough pricewise. It’s also a lovely-jubbly machine – do try one.

Specification

Greenspeed GT3 £1,900
Weight 18.2kg (40lb)
Gears Shimano Capreo/Tiagra derailleur
Gear ratios Low 20″-57″ Medium 27″-79″ High 34″-98″
Brakes Twin Sturmey Archer drums
Brake force (one wheel) 0.3G (both wheels) 0.65G
Tyres Primo Comet 37x349mm
Track 74.5cm
Overall width 82cm
Folded size H52cm W82cm L101cm
Folded volume 430lt (15 cu ft)
Manufacturer Greenspeed web www.greenspeed.com.au mail ian@greenspeed.com.au tel +61 9758 5541
UK Distributor Westcountry Recumbents web www.wrhpv.com mail rob@wrhpv.com tel 0870 7401227

FreeRadical Cargo-kit

freeradical-cargo-kitThe carrying capacity of a conventional bike shouldn’t be underestimated – it’s amazing what you can fit into a decent set of panniers. However, with cycling as my main form of transport, I often wished I could carry heavier or awkwardly-shaped items.The obvious solution was a trailer, and I picked up a great hand-built one, but found that for a number of reasons it didn’t quite suit my needs. Most crucially, with a trailer you only have the extra cargo capacity when you’ve bothered to lug it round with you.

Few people would be willing to keep even the slickest, lightest trailer permanently attached to their bike. If you’re of a well organised persuasion, this probably isn’t a worry, as you’ll just hitch a trailer on when required. But personally I decided I’d like to be able to hop on my bike knowing I could carry a big load whenever the need arose.That’s why I ended up buying a ‘FreeRadical’, a kit designed to turn a regular bike into a cargo bike.

Installation

According to the booklet, ‘installation is meant to be carried out by a professional bicycle mechanic only’. But I enjoy fiddling with bikes, and had enough confidence in my mechanical abilities to have a go.The first task is to remove the rear wheel, chain, rear derailleur and brakes.The FreeRadical frame then simply bolts into the dropouts for the rear wheel, and is also attached near the bottom bracket.This produces an extended bike frame which seems pretty sturdy – I’ve had no problems with mine as yet. Rear derailleur and brakes need to be re-fitted with the extended cables provided with the kit.

…you can even carry passengers… up to a maximum payload of 90kg…

With the rear wheel slotted into place, you’ll find the wheelbase has grown by around 38cm (15 inches), which means extending the chain by attaching the extra 30 inches of links supplied.With everything back together and re-adjusted, the remaining task is to assemble the load-carrying frame.The FreeRadical has four vertical tubes – one pair in front of the rear wheel, and one pair behind. Into these slot two U-shaped racks, one on either side of the wheel, straddled and clamped into place with what the surfer-dude designers have styled a ‘SnapDeck’, but we would call a bit of plywood.

Carrying Stuff

freeradical-cargo-kit-1Load carrying is done primarily in so-called ‘FreeLoaders’: Nylon flaps which attach to the racks. These are open at the top, so shouldn’t be used simply as bags (I initially made that mistake and lost a few things as a result!).The idea is that you put your shopping in bags and put the bags in the FreeLoaders.The open- topped design allows you to carry large or awkwardly- shaped loads, such as wooden planks.

As well as lashing on loads via the FreeLoaders, you can strap big objects onto the SnapDeck platform, and you can even carry passengers this way, up to a maximum payload of 90kg. Footrests are available as an option to make the ride a bit more comfortable! Other options include horizontal racks to give even greater load- carrying capacity. I haven’t tried these, but on the web site there are lots of pictures of sporty right-on types carrying canoes and the like.The full package (bike and FreeRadical), is referred to (with more surf-jargon) as an XtraCycle.

Extending the wheelbase of your bike obviously produces a significant change in handling. I think this is best summarised as an increase in stability with a corresponding decrease in manoeuvrability – a bit like changing from a small-wheeled folder to a conventional road bike. It’s a subjective thing, but I really like the ‘cruiserish’ feel of the XtraCycle.The bike remains nippy enough, and the extra length is a key factor in the bike handling well under loads.The whole assembly adds just over 4kg to the weight of your bike.This does affect acceleration a bit, but not excessively so.

Train Friendly?

Being 38cm (15″) longer and marginally wider at the back than a regular bike, the question of compatibility with public transport is important. In my experience, on trains where bike storage is in a guards van, an XtraCycle slots in no problem.Things become a bit more complicated where bikes are forced to jostle for space with passengers. For instance an XtraCycle will fit fine in the bike space on a Virgin Voyager, provided you remove the front wheel, but on trains with space for only two conventional bikes, an XtraCycle will take up both spaces. And the guard would probably take some ersuading to let it on. Having said all this, in my recent experience you have to be pretty brave to take even a conventional bike on many journeys – I think I’ll follow A to B’s advice and get a folder for the train.

…the design is not well suited to British weather… the SnapDeck absorbed water and warped…

A Few Problems

freeradical-cargo-kit-2Most significantly, the design is not as well suited to British weather as it might be, which is hardly surprising, as the designers are based in Nevada.The FreeRadical frame is made of steel, while the racks that slot into it are aluminium. Given a heavy shower the vertical tubes of the FreeRadical collect water, and corrosion occurs rapidly, all the more so because of the interface between the two metals.Thankfully, this problem can be avoided by wrapping some waterproof tape around the junction between the racks and their sockets. Another damp-related problem I encountered was that after being left outside overnight, the SnapDeck absorbed water and warped. I’ve since painted it with exterior varnish, which seems to have worked.

You may need a few extra parts too. I found the new chain did not mesh properly with some of the gears on my rather old and worn rear cassette.This meant I had to shell out for a new cassette… Not a problem with hub gears, obviously.You may also need to upgrade the brakes for the extra weight, although my V-brakes worked fine.

Conclusions

For me, the FreeRadical has been a big success, enabling me to pootle happily about with large quantities of shopping, recycling, and the occasional friend. I’m sure a trailer would be a more appropriate solution for many people, but I definitely think a FreeRadical is worth considering if you regularly pull heavy loads, or simply fancy trying something a bit different.The ability to carry a passenger will also do wonders for your popularity, and helps to extend the role of the bicycle even further.

Unfortunately XtraCycle doesn’t do itself any favours in the way it brands the product: The skater/surfer terminology grates after a bit, and the web site is full of testimonials from born-again cycling-dudes whose lives have been transformed, which can be a bit off-putting to more cynical British eyes.

Specification

FreeRadical £225 (plus £14 p&p)
Weight (claimed) 4kg (8.8lb)
Maximum load 90kg (200lb)
USA Manufacturer Xtracycle mail infousa@xtracycle.com web www.extracycle.com
UK Distributors (England) Re-Cycle tel 01845 4580854 or 4580758 mail merlin@re-cycle.org
web www.re-cycle.org . (Scotland) Edinburgh Cycle Co-op tel 0131 3371484

Glowbag

glowbagIt’s a measure of just how in tune we are, that we immediately thought a Glowbag was something you planted tomatoes in (don’t bother – home-made compost is just as effective), but it turns out to be a bag that, er, glows.

As walkers, cyclists, equestrians and motorcyclists will knowl, it pays to be seen, and reflective clothing does quite a good job.The trouble with day-glo jackets is that they make you look like a banana. No problem if you’re a fruit fetishist, or the sort of brave soul who really couldn’t care less, but some people object to dressing up like a Belisha beacon to avoid being turned into strawberry jam by an incompetent motorist.

The answer is to dress in fashionable black, but wear something highly fluorescent, such as a Glowbag, which comes (naturally) in fashionable black, with stripes, a triangle, or large rectangle of Scotchlite material.This is the stuff the professionals use, and it throws back light from car headlights to spectacular effect. As the fashionable young people at Glowbag like to say: ‘This is no fluorescent yellow strip! This isn’t about looking like a complete nerd!’ Ah, quite so.

Glowbags come in two types – ‘Grand’ (a 25 litre courier bag), and ‘Midi’.This is much smaller, indeed the two zip-top pouches on the Midi will barely accommodate ‘two cans of Carlsberg’, according to Glowbag, which could mean multiple trips to the off-licence. For unashamedly nerdy but practical types, a couple of tinnies might translate into an Ordnance Survey 1:50,000 map, A to B magazine, wallet, house keys, puncture repair kit and a few basic tools.There’s also a handy little pouch on the strap, that makes a jolly useful home for your mobile phone, provided you’re fashionable enough to own one, and of course, know how to use it.

Our only real criticism is that you have to make a conscious effort to sling the bag behind for it to be effective.They’re also fairly expensive: the small Midi bag costing £21 to £26.50 and the Grand, £52 to £59.The price depends on the amount of Scotchlite in the design, which gives you an idea how expensive the raw material is. Still, street credibility never came cheap.

Glowbag Ltd tel 0207 5822282 mail sales@glowbag.com

Cycles Maximus Pedicab

cycles-maximus-pedicabThere’s a certain romance associated with human power.You know the sort of thing – the bronzed noble savage, pulsating limbs, rippling muscles, incredible loads, and not even a whiff of nitrous oxide. Ooh, enough, enough! The reality – as any gap-year rickshaw pilot will tell you – can be very different. Pedal power can move surprising loads at modest speeds on the flat, but come to a hill and rolling resistance becomes the least of your worries…We regularly drag trailing loads of 70kg uphill to the Post Office, so we know a little about these things (and generally choose an electric bike for the job too).

Out of the blue, we had a call along the lines of the washing powder ads: ‘Would we swap all our regular cycles for a Cycles Maximus Pedicab?’ Living in hilly Somerset, the answer would have been a curt ‘No’, but this machine is rather different, because it comes with power-assistance – either a fairly conventional Heinzmann motor in the front wheel, or a much more exciting chassis-mounted Lynch motor at the rear.With this sort of assistance, rickshaws could be poised to strike out from the flat inner city to become practical load-carriers just about anywhere. It comes at a price, of course: £2,900 for the basic Pedicab or Cargo machine, plus £605 for the Heinzmann power-assist equipment (a great bargain, incidentally), or a healthy £2,095 for the meatier Lynch motor, making a total of £4,995 on the road. If that sounds a bit pricey, remember, we’re talking small van capability here, but without the fuel, servicing, parking tickets, congestion charge, taxation or compulsory insurance.

Despite grumbles from black cab drivers, the practicality of these machines is unquestioned in cities, but could a rickshaw provide practical day-to-day family transport?

Backgroundus

cycles-maximus-pedicab-2Cycles Maximus is the creation of Ian Wood, a Bath publican (owner of drinking establishments, for overseas readers).The HPV business started in a couple of lock- ups back in 1997, when Ian and business partner Tom Nesbitt set to work designing, and ultimately producing, a lighter, faster version of the classic rickshaw, or pedicab as they’re becoming known. In April 2001, the company moved to a 5,000 square foot factory unit, and notched production up a gear.Today, Pedicabs, and increasingly, Cargo trikes, roll off the assembly line at the rate of about one a week, making Cycles Maximus the biggest producer in Europe and very possibly anywhere outside the Third World.Total sales to date exceed 160, of which around 100 work in London, with smaller pockets in York, Edinburgh and elsewhere. Most of the Pedicabs are pedal-powered, carrying passengers over short distances, but Cargo trikes are more likely to include electric-assist and undertake longer journeys with bigger loads.

The basis of the machines is a neat tricycle chassis that can be adapted to carry loads of up to 250kg in the charming, but very practical ‘Cargo Box’, or up to three passengers in a conventional looking, but high-tech rickshaw body.With only three mounting bolts, the body units are easily swapped, and some machines earn a dual living: cargo by day, people by night. Not many Ford Transits do that.

Perhaps most striking at first glance is that nearly half of the trike’s 2.5 metre length is allotted to the rider.The business end – either Pedicab or Cargo body – fits neatly between the rear wheels, mounted as low as is practically possible above the central differential.There’s no suspension as such, but the bodies are rubber-mounted to give a degree of resilience.

The rolling chassis weighs 46kg, to which you must add 29kg for the Pedicab (27.5kg for the Cargo), and 46kg for the optional Lynch power-assist, making a total of 75kg un- powered or 121kg powered.To put this in perspective for cycling types, pedalling an empty un-assisted rickshaw is a bit like riding a tandem with an unproductive eight stone stoker on the back. No great problem on the flat, but hard going on hills.

Most of the Maximus trikes are fitted with SRAMs’ excellent 3×8 gear system – the combination of 3-speed hub and 8-speed derailleur being ideal for the purpose. Bottom gear is 14 inches – very low for a bicycle, but essential on a load-carrying trike.Without power assistance, this mega-granny gear just allows a reasonably fit cyclist to inch the trike up a 10% gradient with a three-child 80kg test load, but only the seriously fit need apply on a daily basis. Once over the top, low range takes you from 14″ to 40″, mid range from 19″ to 55″ and high from 26″ to 75″. If you can find the terrain, that’s high enough to spin up to a conventional bicycle speed.Typically, speed tops out in the 6-12mph region, but small variations in gradient can make a big difference.

Heinzmann-power

cycles-maximus-pedicab-batteries

The batteries (twin on the Heinzmann, large single on the Lynch) intrude into the spacious Cargo Box, but not much

Hills present a major obstacle, pulling speed down to 2mph, one, or nothing, should you be unlucky or completely knackered. That’s where the Heinzmann motor comes in, feeding a little extra zest to the front wheel, as and when required. Designed to give a boost to a conventional bike, the motor can rapidly get out of its depth in the commercial trike world, despite being geared for 12mph, rather than 15mph. Hill starts are a particular challenge, because the stalled motor is being asked to grind slowly away with the sort of load it was never intended for.With 80kg on the back, we just managed to rush a short stretch of 15% (1 in 7.5), which is fortunate because it’s part of our driveway. A restart was beyond us.

The Heinzmann-assisted machine will tackle gradients of up to 8% at modest speed with a load in the 50-80kg range, but certainly not fully laden. Once speed falls below 6mph or so, the motor rapidly wilts, leaving you more or less on your own. If the load and/or terrain exceed these limits, you need something a bit hunkier.

Lynch-power

This is a much more sophisticated package – a top quality motor driving a layshaft via its own freewheel. Everything, from the wiring to the mechanical bits, is well engineered, and it needs to be, because the Lynch motor is a seriously powerful beast, designed for heavy commercial use.

Engaging the motor is dead easy.You start by turning an ‘ignition’ key, then feed power in with a twistgrip throttle.To stay within the electric tricycle legislation, Cycles Maximus has provided a torque-sensing switch, so power is only available when you’re pedalling, but you don’t need to be moving, so hill starts are easy. If pedal effort drops below a pre-set limit, the motor resets itself, and you have to pedal harder, wind the throttle back and start again – a good safety feature.

cycles-maximus-pedicab-speed-vs-power-consumptionThe motor is continuously rated at 250 watts, which brings it within current electric tricycle legislation, so the Lynch- motored trike doesn’t need an MOT, tax disc and all the rest.With a modest load and on modest gradients, 250 watts will keep you chugging gently along all day. Our motor was geared for a comfortable 9mph, but the gearing is up to you, provided assistance is not available above 15mph.

Hit a gradient and the Lynch motor grunts, hardens its note and climbs whatever you put in front of it.The steeper the climb, the more it buckles down and the more power it produces. For example, with Castle Cary’s 10% gradients, and loads of 50-80kg, speed falls to 7 or 8mph and power input from the motor hits 700 watts or so. But restart on a serious gradient with a full load, and power can peak at anything up to 3.3 kw, or nearly five horsepower…We can’t vouch for the accuracy of our test equipment at this sort of level, but the figures are of little relevance, because in everyday use, speed hardly ever falls below 6mph, or power above 1,500 watts.

Maximum power can only be used in short bursts, but it’s nice to know you can restart on more or less any gradient with more or less any load.This is particularly important with the Lynch motor because the heavy-duty layshafts and cogs don’t leave space for the SRAM 3×8 gear system, so you’re stuck with a standard Shimano Deore derailleur giving eight gears of (in our case) 21″ to 58″. Obviously, battery condition is something you want to know about – the Lynch is more likely to be carrying heavy loads in hilly areas, and it doesn’t have the gearing to get home if something goes wrong.

So what about that romantic human-power stuff? Well, it’s true that your puny efforts can begin to look a bit sad against the giant-slaying Lynch, but for much of the time the motor rests or hums gently, leaving a human-powered machine to delight the purists.

On the Road

For a bicyclist, the first, and rather unnerving, impressions are: (a) it doesn’t lean into corners, and (b), if you try to ‘lean-steer’ you will simply veer off the road. After a few minutes you get the hang of this, before being unnerved all over again on the first adverse road camber, because then it will lean and you can’t bring it upright.

Handling is merely a concept at 8mph, but rather more important at 30mph…

Some people recovered their composure fairly quickly, but it has to be said that others failed to adjust and were convinced they never would. Even if you master three- wheeled cornering, the conventional looking front forks can lead you to forget that you’re piloting a vehicle 121cm (48″) wide above the seat. Look over your shoulder to place the wheels through a gap and you’ll find that the Pedicab is three centimetres narrower down there… None of this applies to the Cargo variant, which has a lower, narrower body.

Another advantage with the Cargo is excellent rearward visibility, whereas the Pedicab roof is rather awkwardly at driver’s eye height. This turns out to be important, because unlike a bicycle – even a bicycle with a trailer attached – if you’re driving something 121cm wide at 8mph, motorised traffic soon gets grumpy, and they’ll be fighting to squeeze past.

If you’re the sort of person who enjoys winding up motorists, a Pedicab will give you enormous pleasure, but for cyclists more used to sharing the roadspace in reasonable equanimity, a long queue can be embarrassing. Other people’s jams cause problems too, so jam-phobics should stick to something more traditional. Once you’re stuck, you’ll be watching cyclists wiggle through the gaps and telling your passengers what a bloody nuisance they are, just like any other cab driver.

If you’re used to a bicycle, parking a 1.2 metre-wide three-wheeler sounds like a nightmare, but it’s easy.The Cycles Maximus is small by car standards, and with a bit of practice, it can be turned in its 2.5 metre length, enabling it to squeeze into impossible spaces. If you get boxed in by an ignorant motorist, the trike is easy enough to lift sideways – you can often get away with parking side-on too.

On the open road, the Lynch motor does its bit in the 6mph to 8mph region, leaving the rider to play with the top two or three gears. Maximum velocity depends how fast you can pedal – 12mph is easy, and 14mph is feasible if your passenger is late for work.

Once on a downgrade, speed climbs rapidly to 30mph plus – not bad going for the equivalent of a covered wagon. As one might expect, a vehicle with a drag coefficient of a large brick, sitting on three motorcycle tyres, doesn’t roll very well.We managed an average of only 9.2mph on our test hill, and at that speed wind resistance doesn’t have a great effect, so much of the blame must lie with the tyres and mechanical bits. Strangely, with the more streamlined weather shield fitted, rolling speed fell to 8.5mph, which suggests a massive increase in drag.

Handling is merely an esoteric concept at 8mph, but rather more important at 30mph.The rear wheels do exactly what you ask, but the single front tyre sometimes fights for grip on fast turns, causing mild understeer (ie, it threatens to go straight on). Push too hard, particularly when empty on an adverse camber, and the trike will lift an inside wheel, although a touch on the rear brake should get things back under control.

With a maximum gross weight of nearly half a ton, brakes are important and the same attention to detail applies here as elsewhere.The rear wheels are restrained by a pair of Hope hydraulic discs, which are very powerful, but without the surface area for prolonged use.With an empty trike, it’s easy to lock the rear wheels, and we achieved a maximum stop of only 0.38G unloaded. But there’s plenty more power available, so (up to a point) the greater the load, the more effective the rear discs become.

The front Magura hydraulic rim brake would be pretty effective on a bicycle, but on such a heavy vehicle, it struggles a bit.We managed a maximum stop of 0.39G using the front brake – this time the limit being brake lever effort rather than locked wheels. Heaving on both anchors results in an emergency stop of 0.6G, which is good, but not scintillating.The front brake comes with a little parking clip, which is essential, but not really up to holding a loaded trike on a gradient.

With hard use, the rear discs overheat very rapidly, although the brakes fail safe, progressively seizing on until the discs have cooled.This is unlikely to occur in central London, but it’s easily done in Somerset.The only answer is to think ahead and go easy on the brakes on long descents. Electric regenerative braking would put a bit of oomph back into the battery and ease the strain on the brakes – it’s being considered.

Equipment

cycles-maximus-pedicab-weather-shield

The weather shield is a great favourite, but it increases wind resistance

For the driver, creature comforts are sadly lacking, but there’s a wonderful ding-dong bell to play with.We’d like to see a decent speedometer too, because E.T.A, current time, ride time, average speed, trip and overall mileage are pretty useful in a business environment.The load- carrying Cargo comes with a nicely engineered aluminium body and drop tailgate. If you know what a Euro Pallet is, the load area of 122cm x 90cm x 96cm will apparently accommodate one, but  batteries reduce the space a little on powered versions. Rain and prying eyes are kept at bay with a weatherproof hood, fastened to the body with velcro strips, while zips front and rear allow panels to be rolled up for access or ventilation.The cover is easy to remove too.

The Pedicab has a wider and more complex body.The seat is made of a ventilated rubberised material, which is useful, because it will get wet.The hood is generously proportioned and secured with velcro straps, making it easy to remove.The frame is mounted on gas-struts enabling it to tilt downwards – useful should you want to tip water off, but primarily designed so that vandals will fall off and do themselves an injury.

At low speed, the roof keeps light rain at bay, although water tends to pool on top, then sluice all over the driver on the first downhill, to the great amusement of passengers. For monsoon conditions, the weather shield hooks under the roof and more or less eliminates wind, rain and spray. But fitting is a five-minute job, so don’t wait for the rain to start falling.

Lights are adequate for city use – a pair of battery LED rear lights and a Nordlicht dynamo with Busch & Müller Oval front light. But on the wider Pedicab in particular, we’d like to see white/red repeater lights on the extremities, because it looks too much like a bicycle for comfort.The hefty 12 volt supply for the motor could be tapped to power much better lights too.We’d suggest optional rear-facing indicators and even brake lights. Car equipment is relatively cheap and very powerful.

Range

With supplementary bananas, the human-powered jobs will run all day, but the electric-assist batteries have a finite life.We only had a brief time with the Heinzmann-powered trike, but from our Heinzmann experience, we’d suggest 20 to 40 miles from the 984 watt/hour lead-acid batteries, depending on load, gradients and the amount the motor is used.The more powerful Lynch is a faster hill climber, with a smaller 828 watt/hour battery, so range is rather less. Around town, carrying modest 50-80kg loads, we achieved 17 – 181/2 miles, at an average speed of 7.7 to 9.3mph… heady stuff.

…the machine ambles up killer hills, even the 14% kind…

Daft wombats that we are, we couldn’t resist testing the Pedicab over the 171/2 miles of switchback roads and killer climbs, more commonly known as the A to B mountain course.With a good electric bike, this ride takes an hour and twenty minutes, but with a gross weight of over 300kg, including a realistic 100kg load – Alexander (43/4), Jeffrey (8), Alice (10), charger and tools – we were reckoning on a couple of hours.

As expected, the machine ambled up the killer hills, even the 14% (1 in 7) kind, at a steady 6-8mph, and we hit some wild speeds on the descents (31mph, would you believe). But a long trip of this kind can be soul-destroying work for the rider, because the motor only assists up to 8mph. At higher speed, you soon lose the will to live, speed drops back to 8mph, and the cycle repeats itself.

The Lynch motor comes with a sophisticated fuel meter, graduated in ten steps between empty and full, but it’s far from linear.The first light went out at 6 miles, the second at 9.7, third at 12.6, forth at 16 and 5th at 17.1 miles, within sight of journey’s end. That might sound like half a tank, but in fact there were only a couple of miles in reserve. Maximum range in hilly country, carrying 100kg, is 19 miles, but unassisted progress is so scary a prospect, that we wouldn’t recommend trips in excess of 15 miles or so.

Average speed turned out to be 10mph, giving a door-to-door journey time – including two punctures and a brief stop for refreshments – of two hours. Strangely, the trikes’ chunky 23-inch moped tyres proved particularly vulnerable to thorns.We say this because the machine was accompanied by the Greenspeed trike (on racy Primo slicks) and our Giant Lafree, neither of which suffered any harm. Both punctures were fixed with Tyreweld foam, although rather disappointingly, both were flat again by journey’s end.With the frame supported on bricks, tyre repairs are straightforward, although bicycle tyre levers might not be up to dealing with tough motorcycle rubber.

cycles-maximus-pedicab-8Thanks to a state-of- the-art German charger, recharging is reasonably quick: A 90% charge takes 41/2 hours, followed by a lengthy ‘trickle’ charge, completed in another four hours or so. Unfortunately, we set off after four hours, which took the machine only 121/2 miles.That’s much less than we expected, which might have something to do with the drag characteristics of the weather shield, which was fitted on the way home to keep the 100kg load cheerful.

…one cyclist transported three children in safety and comfort… that’s hard to do without a car…

If you haven’t ridden a loaded rickshaw up a 17% (1 in 6) gradient, let us try to set the picture.With a cyclist standing on the Note the battery under the seat. The motor is behind the differential pedals in the bottom 21″ gear, and two other adults and most of the 100kg load pushing behind, we just inched our way over the summit. In other words, it’s something you might want to do once in life, but never again.The last four flattish miles are lost in mists of pain.

To be fair, this is testing in extremis, and should not be taken too seriously.Yes, we had a few problems, but while the battery held out, one relatively relaxed cyclist transported three children a considerable distance in safety and comfort – something that would otherwise be hard to do without a car. In an easily graded city, Lynch-motor Pedicabs will run for a full shift, but carrying heavy loads in hillier areas, active duty can be two hours or even less.

Conclusion

It’s crazy, but the ridiculous Powershift Grants (see A to B 35) cannot be applied to a Cycles Maximus Cargo or Pedicab because, er, they have pedals. If you have a commercial or private use for such a machine and would like a hefty rebate on the purchase cost, we can only suggest you lobby your MP.

The Cycles Maximus machines successfully bridge the gap between the humble bicycle and diesel-fuelled delivery vans and taxis. Even the Lynch-powered machine is legally a pedal tricycle according to the latest interpretation of the rules, so it can go anywhere a bicycle can go (provided there’s room, of course) and park without risk of a ticket (although the police could presumably invoke the obstruction laws).

For commercial use, these machines make a lot of sense, and the electric options should help to spread the assisted-pedal power message.The Heinzmann gives a gentle push at a reasonable cost, and the Lynch – although expensive – has most of the capabilities of its smaller infernal-combustion cousins, but without the downsides.

We also think a community or local authority-owned machine would find all sorts of uses, including a daily school run.The Pedicab (Bike Bus in Alexander-speak) will transport three children in comfort, and the Cargo (Bike Van) could be adapted to carry four or even six small ‘uns, replacing a veritable fleet of motors. Over short distances, door-to- door journey times compare well with a car, and the young (and young-at-heart) absolutely love travelling this way.Why does everyone choose the dreariest way of getting children to school? Kids really don’t want to be strapped into a bulbous four-wheel-drive with tinted windows – they want to wave, shout at their friends and generally release a bit of energy. For smaller children, the Pedicab is the last word in cool transportation.

Coming from a bicycle background, we wouldn’t swap our vehicles for a Pedicab.True, we need a shed full of folding bikes, a trailer bike, child/luggage trailer and power-assisted bike, to achieve much the same thing, but these individual machines give greater flexibility, no parking hassles, and higher speed (almost double). But if we had several children – especially if we wanted to dispose of a second car – we would seriously consider it.The concept of travelling together as a family, and offering lifts to friends, relatives and passers- by, gave priceless entertainment.We’ll certainly miss the Bike Bus.

Specification

Cycles Maximus Cargo or Pedicab £2,900
Heinzmann power-assist £605 extra
Lynch power-assist £2,090 extra
Weight (unpowered) 75kg (powered) 121kg
Payload 250kg
Overall width (Pedicab) 121cm (Cargo) 118cm
Overall Length (Pedicab) 250cm (Cargo) 234cm
Gear range (non-Lynch motor) 14″ – 75″ (Lynch motor) 21″ – 58″
Battery type Sealed lead-acid
Battery capacity (Heinzmann) 984wh (Lynch) 828wh
Range (Heinzmann) 40 miles est. (Lynch) 19 miles
UK Manufacturer Cycles Maximus tel 01225 319414 mail info@cyclesmaximus.com web www.cyclesmaximus.com

Top-draw Dynamos – Bush & Müller Dymotec S12 & Dynosys LightSpin

bush-and-muller-dymotecDynamo lights have many advantages.They’re always on call, lightweight, and extra- bright, but traditional dynamos are noisy, inefficient and unreliable.These days, there’s a renewed interest in hub dynamos, which are virtually silent and more reliable, but expensive to buy and fit.We’ve looked at the best bottle dynamos we could find, to see if they’re: (a) worth the extra over a conventional bottle and/or (b) comparable to a hub.

Two manufacturers dominate this business – Swiss company Dynosys, manufacturer of the LightSpin, and Busch & Müller from Germany, manufacturer of the Dymotec.The LightSpin is basically a high-tech version of a conventional six volt bottle dynamo, with improved bearings and electronic voltage control, while the Dymotec comes in three forms: the ‘6’, a more efficient version of a conventional dynamo, the ‘S6’, like the ‘6’, but with voltage control, and the ‘S12’, with everything else, plus a greater output. All can be fitted in place of a conventional bottle or hub dynamo except for the S12 which has an output of 12 volts (all other systems are six volt) and thus needs dedicated lamps, or hard-to-obtain 12 volt bulbs if upgrading older (ie, electronic-free) lamps.

While we’re on the subject, if adding a new bottle to an old system, it’s worth bearing in mind that some ‘medium-tech’ lamps may contain zener diodes to dump surplus voltage and improve bulb life.With the exception of the basic Dymotec 6, these posh-end dynamos contain more sophisticated voltage control and should not be used with zener diodes, because the dynamo will do its best to supply power to the bulbs and zener, which will simply throw the surplus overboard. If in doubt, it’s a good idea to replace the dynamo and lamps at the same time.

We’ve tested the LightSpin against the top-of-the-range B&M Dymotec S12.The 6 and S6 are cheaper, and broadly similar, but with lower output. For the purposes of making the test as realistic as possible, we fitted the dynamos to a hack bike with slightly wobbly wheels, although if spending this sort of money you’d be well advised to have the wheels trued, because a wobbly wheel will reduce efficiency. Both the designs dealt manfully with wobbles and inclement weather.

Dymotec S12

bush-and-muller-dymotec-speed-vs-powerThe Dymotec 6 costs £38, the S6 £110, and the S12 (complete with 12v versions of the Lumotec Oval Plus front light and Toplight Plus rear lights), no less than £300. Sounds like a reasonable budget for a bicycle. But for engineers everywhere, this is more or less the dream spec for a dynamo: 12 volts, 6.2 watts and 60% efficiency. For the rest of us, let us just say it’s solidly made, reliable and efficient.

So, what do all the numbers mean? As any woman will tell you, it’s largely a man thing: big numbers meaning a generous wallet, unrivalled fertility, and so forth, but a 12 volt dynamo really does make some sense.

Most battery lights are three volts, and dynamos six volts – the voltage being a measure of the electrical ‘pressure’. On its own, this tells us nothing about the light output, but the greater the pressure, the easier it is for the power to fight its way through those embarrassing dodgy joints held together with sticky tape. In short, a 12 volt system is more reliable.

Efficiency is the difference between the power you put in and the electrical power that comes out of the dynamo. Some are atrociously inefficient, turning only 20-30% of your hard won effort into light, while the rest floats off into the night as heat and noise. Fortunately, dynamos are small, absorbing 15 watts or less for an output of three useful watts. For those who’ve forgotten their school physics, voltage (electrical pressure) multiplied by amps (the current or volume of electricity) equals watts – the measurement of electric power.

Fifteen watts doesn’t sound much, but if you’re tooling gently home on a bicycle at a modest 13mph, your total power output may be less than 75 watts, so a crummy old dynamo could be absorbing nearly a quarter of your leg power.

Better quality bearings, and other much more complicated things, bring greater efficiency. Busch & Müller claim 40% for the 6, 55% for the S6, and 60% for the S12.That efficiency is used to cut the overall power consumption on the six volt units, but with the S12, B&M has chosen instead to provide a greater output: 6.2 watts, plus the 40% chucked away as heat, giving a total drain on your legs of 10.3 watts.All a bit complicated, but the result is a bit less effort, twice as much light, and a very tiny reduction in global warming.

In practice, our test yielded a whopping peak output of 8.7 watts (the extra power recharges the standlight lamps in the first few minutes of operation). But with a steady output of 15.2 volts above 8mph, we suspect the S12 might be powerful enough to eat bulbs relatively quickly. Don’t care, eh? You will when you find the bulbs cost £12.99 each.

Rolling resistance is barely discernible.When we tested a down-market three watt dynamo in October, it knocked 1.4 mph off our typical coasting speed.The S12 (generating 8.7 watts), only reduces the coasting speed by 0.5 mph – noticeable, but insignificant.

Fitting

…not a bad chat-up line…you could ask them to come up and inspect your zener diodes…

Fitting the S12 is quite straightforward, and we managed to assemble a complete system including the front and rear lamps in about an hour. One bit of advice – do solder the connectors if you can.There’s no point in spending £300 just to see the wiring fall apart on the first soggy night. If you don’t have the technology, trim the wires to length and seek out a man or woman with a soldering iron (not a bad chat-up line, all things considered – you could ask them to come up and inspect your zener diodes too). Otherwise, assembly is fairly self-evident.The dynamo needs to be carefully aligned, like any other, but the Dymotec units also feature a crafty contact pressure adjustment, which should be set as low as possible for any particular tyre/weather combination. If the lights flicker, increase the pressure a bit. For rough conditions, the rubber roller can be swapped (hardly a roadside job) for B&M’s ‘weather-proof’ design, a rotary wire brush that would do a decent job of buffing up your small parts.This should be kept well away from frail tyre sidewalls and small fingers for obvious reasons. B&M make the point that it should only be used ‘temporarily’ in ‘rainy, snowy or icy’ conditions.We didn’t need it, but it was nice to know it was there.

Light output

bush-and-muller-dymotec-lightWe tested the S12 with Busch & Müller’s wonderful Lumotec Oval Plus front lamp and Toplight Plus rear lamp, produced in 12 volt versions specifically for this dynamo. Both have a standlight function too – the rear LEDs continue to burn at full brightness for about five minutes, while the front switches to a single white LED that lasts for ‘at least’ ten minutes. Ever tried waiting for a standlight to go out when there’s something good on the telly? Should your unsoldered connectors drop off, the front standlight is as powerful as some elderly filament bulbs, and easily bright enough to get you home.

As for the halogen main beam, don’t expect two or three times as much light as normal, just because you’re generating two or three times as much power, but in terms of brightness and spread, the Lumotec is unrivalled. Country roads are easily navigated at speed, and oncoming cars tend to assume you’re motorised, treating you with a bit of respect. Our only criticism is that enough light scatters through the transparent rim of the lens to dazzle the rider in open country, which is a bit counter- productive.The easy answer is a strip of black masking tape, but surely this should be sorted at source?

LightSpin

dynosys-lightspin-dynamoUnlike the B&M S12, this is a six volt device, so you can use it with conventional six volt lamps, provided you seek and destroy those pesky zener diodes. It’s also relatively cheap at £70 – a full £40 less than the B&M S6, which has a lower output. Efficiency is claimed to be 65-75%, so with our measured power output of only 2.6 watts, we estimate a power requirement of less than four watts.With such a low demand, the wheel can be spun quite easily – you can’t feel it on the road.The coasting speed was reduced from 15.3 to 15.2 mph – a barely discernible effect.

Incidentally, the low power output on our graph doesn’t necessarily make this a seven stone weakling amongst dynamos. Traditional bottle dynamos tend to call it a day at three watts, but the LightSpin provides whatever the bulb demands, up to a recommended maximum of 4.8 watts. It just happens that our bulb combination demanded only 2.6 watts. With this dynamo (and the B&M S6 too) it is permissible to fit a three watt bulb at the front and 0.6 watt at the rear, making 3.6 watts in all.

We paired the LightSpin with the neat little Hella Micro FF front lamp.The result was noticeably less exciting than the B&M S12, but the lamp throws a smaller, well defined pool of light just where you want it. Or at least, it does if you take great care aiming the lamp.

Conclusion

Value for money is a difficult concept at this level. After all, you can buy a basic dynamo for less than £10, but we wouldn’t recommend cutting corners to that extent if you commute on a regular basis.The B&M in particular is frighteningly expensive, but it offers unrivalled light output.The cheaper B&Ms and the Lightspin have a more conventional power output, but great efficiency.

They’re all better than the cooking variety, but are they as good as a hub dynamo? They’re certainly noisier, and compared to the hubs we’ve tried, the useful power kicks in at a slightly higher speed – 5mph instead of 4mph.That might seem irrelevant, but a hub will keep the lights close to full brightness at a smart walking pace, whereas the bottle dynamos will not.They’re relatively vulnerable too, both to the elements and vandalism.

On the positive side, a bottle dynamo is quick, easy and cheap to fit, and there’s no drag when it’s turned away from the tyre, although drag has been virtually eliminated from the hubs these days anyway.

Our instincts are moving towards the weather-proof, no-nonsense hub, but there are plenty of reasons why you might prefer something easier to fit, and if you want hub performance from a bottle, one of these might suit. If you’re looking for low rolling resistance above all else, the LightSpin is the best, but if power matters, go for B&M’s S12. There’s enough oomph here to recharge a mobile phone, or even a lap-top, provided you can find a suitable adaptor.

Specification

Dymotec S12 (c/w lamps) £300
Power output (claimed) 6.2 watts
Efficiency (claimed) 60%
Manufacturer Busch & Müller tel +49 2354 9156 mail info@bumm.de web www.bumm.de
UK distributor AMBA Marketing (UK) tel 01392 840030 mail sales@amba-marketing.com

Dynosys LightSpin £70
Power output (claimed) 4.8 watts
Efficiency (claimed) 65-75%
Manufacturer Dynosys tel +41 62827 4828 mail info@dynosys-ag.ch web www.dynosys-ag.ch
UK Distributor Gearshift tel 0700 0700 531 web www.gearshift.co.uk

Zero Shaft-drive

zero-shaft-drive-folding-bikeShaft drives look great on paper, trading that grubby old chain for a completely sealed unit – no gear teeth, no oil, no grime, and no hassle. In reality, they’re relatively inefficient, noisy, heavy and expensive. Altering the gear ratio is a major engineering job, and even measuring the ratio can be complex. Forget what the salesmen say.The chain remains with us today – essentially unchanged for over 100 years – because it’s a damn good solution, unmatched by older and more recent inventions, such as the toothed rubber belt, shaft, oscillating rods, hydraulic, electric and all the rest.

Having demolished the genre, we couldn’t resist a review of Zero’s shaft-drive folding bike, partly because we think a folder brings a novel set of problems to which a shaft- drive is particularly well suited, but also because it’s a really pleasant little machine.

For £475 (about the same as the Giant Halfway) you get a simple, rugged 20-inch wheel fold-in-half bike, with V-brakes and Shimano Nexus 3-speed hub. Is it a better buy than a conventional 20-inch folder?

How it Works

bicycle-crank-shaft

Crank shaft (top), bearing assembly (right) and crank bevel gear (left)

Zero, the Bristol-based importer of shaft-driven bicycles, make no bones about the origins of the folding derivative.Taiwanese manufacturer Sussex sent over a rather heavy steel folder, but there was some interest, so a deal was done for supply of a lighter alloy-framed version, and this is it.

The business end is simple in terms of components, but no doubt fairly complex to manufacture.Where the bottom bracket bearings would normally be, there’s a large shell containing two substantial ball bearings and a shaft with a bevel drive cog splined loosely to it.We’re not over-keen on this design, because bevel gears exert forces in all sorts of directions. Only time will tell whether the splines are sufficiently robust – if they wear out, the unit will probably have to be scrapped. From the bevel gear, drive is transferred through 90 degrees, along a shaft to the rear wheel, where another pair of bevel gears transfer the pedal effort to a conventional geared hub.

Right-angle gears need to be precisely machined and installed if they’re to operate smoothly and quietly.This system can be a little noisy, because alignment between the bits and pieces is not all it might be (we’ll come to that), but the efficiency feels good – certainly streets ahead of a toothed rubber belt, for example. Zero claims efficiency similar to a chain drive, but we’ll stick with Bicycle Science, which quotes figures of ‘up to 98.5%’ for a chain drive and 92% for a shaft drive, admittedly an early 20th Century example, when such things were last in vogue. From a seat-of-the-pants observation we’d say that figure was probably a bit pessimistic, but losses there certainly are, compounded by the somewhat inefficient Nexus hub.

The bearings and cogs are pre-greased, but they’re not packed with grease and the assembly is not sealed, so if you were to ride through deep salt water for example, the system would need a thorough service.There’s a grease-point at the front, but this only lubricates the front bevel gears, not the bearings. At the rear, the assembly is effectively open to the elements, because of the way the rear wheel pops out.You whip off a plastic cover plate and slide the wheel back complete with its bevel gear. Grubby water can, and will, find its way in here, so the rear cogs are quite exposed. Not as exposed as a typical chain, of course, but by no means safe from the elements.

The Zero arrived with junior 150mm cranks – a strict no-no unless you’re a junior, or an adult with particularly bijou inside leg measurements.This felt most peculiar, but when swapped for more conventional 170mm cranks, the folder felt relatively normal. Not quite normal, because the gears produce a low hum, which can be felt as a slight roughness through the pedals. Incidentally, if you do go for 170mm cranks, the bottom bracket is a bit low, so the pedals are liable to hit the ground on sharp turns.

Gearing is effectively fixed, and although the ratios are on the low side, they’re an acceptable compromise at 30″, 40″ and 55″. First gear will climb reasonable inclines and top will just see you up to a passable cruising speed. For riding short distances in an uppy- downy sort of town you might be all right, but 55 inches is too low for spinning along on the flat with a following breeze.Take it or leave it – the ratios are not for changing.

On the road, the bike feels stable and quite sprightly. It’s easy to ride hands off, and the frame is surprisingly rigid, even when riding out of the saddle. Sussex recommend greasing the drive-shaft at 500km and every 4-6 months thereafter.We mention this because our bike developed some strange squeaking noises within a mile or two. Grease at the rear made no difference (simply remove the plastic cover and spoon it in), but a few strokes with a grease gun at the front solved the problem.What we can’t tell you is how the shaft will survive in the longer term. In theory it will last for decades, but if muddy water gets in, it could grind itself to bits in a few weeks.

…wheel location is rather vague… the drive could do itself a whoopsie…

Equipment

Every thing is unbranded, but by no means the worse for that.The V-brakes have smart alloy levers and work well enough, although the rear brake is hampered by a long and rather convoluted cable run. Both the gear and brake cables are forced into some excruciating positions when folded, so we wouldn’t expect them to last very long.Tyres are Kenda Kontacts – yet another 47-406mm (20-inch) design from this prolific Taiwanese manufacturer.The descent speed of 13.6mph on our test hill is the sort of figure we expect to see from good 16-inch tyres these days, so a relatively poor performance for a 20-inch bike. Mudguards are silvery plastic and unusually generous for a machine of this kind, offering reasonable weather protection, although the front could do with a mudflap.

bevel-gear-bicycle-shaft-drive

With the plastic cover removed, the rear bevel gear looks rather exposed

Should you be worried, the rear wheel is easy to remove. First, the plastic cap comes off the shaft housing, then the mudguard stays, because a horizontal drop-out means the wheel has to be removed from behind.With the gear shifter removed and the wheel bolts loosened, the wheel is free. It’s different, but no more difficult than normal.

Reassembly is a bit more critical. Engineering types may be wondering how the wheel bevel gear is accurately relocated in relation to the shaft bevel – it isn’t, or at least, not with precision one might expect. A the flanged hub nut fits into a recess in the  frame, and that’s it. On the other side of the wheel, location is rather vague, and assembly is not helped by the propstand, which mounts on a splined washer that also locates the hub and acts as an anti-rotation washer. It’s much too fiddly, and if you fail to fit these bits together correctly, the drive could slip, run roughly, or do itself a whoopsie. To be fair, derailleurs require some meticulous fiddling too, but that’s no excuse.

Both the saddle stem and handlebar stem are adjustable – the saddle from 75-96cm from the ground, and the bars from 101-110cm.That saddle height is broadly similar to the Micro or Brompton, but the bars are unusually tall, giving what some people would regard as a rather upright stance. Fine tuning of the saddle is easy, thanks to a nice micro- adjust seat post.

Folding

zero-shaft-drive-folding-bike-foldedSussex markets the steel-framed shaft-drive folder quite widely (you can buy it in the US for $385), but the alloy-framed bike is a more substantial, attractive, and unusually cleanly styled machine.The frame is finished (rather unnecessarily one might think) in lustrous silver metallic paint.The main hinge is a monstrous alloy block in classic Far Eastern style, but it works well enough and incorporates a clever safety device.The pin carrying the quick-release runs in the rear part of the hinge, and when engaged, it drops into a hole in the front part, locking the hinge shut. Even when the quick-release is unfastened, the hinge will not open until the pin is lifted. Simple and effective.The lighter handlebar stem hinge has a similar fitting.

Bikes like this tend to be tricky to fold, but the Zero does the job easily, quickly and without oily fingers.This is where a shaft drive really pays dividends, because you can grab the bike anywhere you please without getting a sticky surprise, and once folded, there’s no oily chainring to snag passers-by or make a hole in the carpet.

With both hinges released, the frame folds back on itself and you can choose whether to keep the front wheel pointing forward, Brompton style (in this case placing the handlebars between the wheels), or not, Dahon style, which puts the bars on the outside, leaving the cables rather vulnerable. Folded size Dahon style is 41.9cm wide by 61cm tall and 75cm long, giving a neat folded package of 191.5 litres or 6.8 cubic feet: almost identical to the similar Dahon Vitesse. Folded Brompton style, the package is both longer and taller, with a volume of 233 litres, or 8.3 cubic feet. Like most bicycles of this type, the Zero has no mechanism to keep the folded bike together, but Zero supply some nice velcro straps.

The folding pedals (the bike only actually needs one) are similar to the old VP – you pull out a locking plate and the pedal drops down leaving a rather large bearing housing. Branded Sunshine, they’re new to us, and not very clever. We’d advise Sussex to buy a few Next pedals, because they’re just that bit better in every respect.

The Zero folder weighs 13.8kg (30.4lb).That compares quite well with cheap and nasty 20-inch machines, but it’s about a kilogram heavier than the elegant Vitesse, which is exactly the penalty Sussex and Zero claim you’ll be paying.

Conclusion

For all its faults – primarily the 150mm cranks and 55″ top gear – we like the Zero folder and think it could make the basis of a low-maintenance canal path commuter, but only for smaller people. Make sure to ask for longer cranks, and to avoid fiddling with that rear wheel, we’d certainly want to fit puncture-resistant tyres (such as the Schwalbe Marathon Plus, just released in 20-inch form).That leaves only the brakes to go wrong, which they’re bound to do, now we’ve said that.

Price-wise, the Zero is in a weak position in a highly competitive market.You could buy two acceptable Dahons for £475, or spend the money on one well-equipped alternative, such as the Trek F400, or the stylish Giant Halfway. If you opt for 16-inch wheels, the Brompton L3 is lighter, a better folder, faster on the road, and cheaper.

Normally such comparisons would be the kiss of death for a newcomer, but the Zero has a certain indefinable something that keeps it in contention. It won’t become a design classic, but it’s different, and sometimes that’s enough.

Specification

Zero Folder £475
Weight 13.8kg (30.4lb)
Folded dimensions W41.9cm H61cm L75cm
Folded volume 191.5 litres (6.8cu ft)
Gears Shimano 3-speed hub
Ratios 30″ 40″ 55″
Tyres Kenda Kontact 47-406mm
Manufacturer Sussex Enterprises web www.sussex.com.tw
UK distributor Zero Cycles tel 01454 316563 mail info@zerocycles.co.uk

Brompton 5-speed Upgrade

brompton-5-speed-hub-upgrade

Old mechanism (front) and new (behind). They are effectively identical, except for the longer axle on the new item. Note the old and new locknuts.

Once upon a time the finest hub gears in the world were churned out from a factory in Nottingham, many finding homes in the Raleigh bicycles made just across the Triumph Road.The sad demise of Sturmey Archer in the autumn of 2000 is a subject we’ve returned to many times. For A to B newbies, this healthy company was brought down by a combination of corporate greed and downright stupidity, resulting in Sturmey being handed to a bunch of asset-strippers, who bled the company dry in a few weeks and chucked out a life-less corpse, the remnants being shipped to Taiwan by Sunrace.

One of the biggest potential losers was Brompton, a company with a full order-book for a folding bike designed specifically for the Sturmey 3 and 5-speed hub gears. In the final weeks, some hastily arranged heavy transport brought a reasonable stock of hubs down to London, giving a breathing space for the bikes to be adapted to accept the German/US SRAM hubs.

The excellent 3-speed SRAM worked well, but the 5-speed was much too wide for the bike. Brompton was forced to become a 3-speed manufacturer for a while, until its own 2-speed derailleur entered production in May 2002 and was fitted alongside the SRAM to produce the elegant 2×3-speed L6 and T6 Bromptons.

…the Sturmey 5-speed wasn’t the most reliable of hub gears.. thanks primarily to poor adjustment…

Meanwhile, Sturmey 5-speed spares were running low – a potential problem for the estimated 20,000 5-speed Bromptons, and countless Moultons, Bickertons and Micros in regular use worldwide. Most bikes could be adapted to take a SRAM 5- speed hub, but the Brompton could not. Conversion to 2×3 spec is not viable either, because the parts alone (3- speed SRAM and wheel, rear frame, cables, changer and 2-speed derailleur kit) cost more than the bike is worth.

In early 2001, Sunrace put the Sturmey 3-speed back into production in Taiwan, and things began to look a little brighter. In late 2002 the 5-speed hub returned too, and although very different on the outside, it was almost identical internally to the ‘ball- locking’ hubs fitted to the Brompton in the last year or so of UK production. Not quite identical, but we’ll come to that.

Can this hub – produced three years later, and 10,000 miles from Nottingham – really be fitted to an elderly 5-speed Brompton? It turns out that it can, and for a reasonable cost, new Sunrace-Sturmey ‘internals’ could revitalise your old folder.

It has to be said that the Sturmey 5-speed was not the most reliable of hubs – a fair number of machines losing one or more gears, thanks primarily to poor adjustment, made worse by a rather woolly gear-shift action. Broken axles were relatively common too.

The ‘ball locking’ mechanism was introduced to hold the hub more positively in gear. Ironically, it came into production just a year or so before the company was dragged under, but the tooling and expertise were kept together, and when production restarted in Taiwan, it was natural that the latest system would be used.

Buying the Bits

brompton-5-speed-hub-upgrade-1

All the grime will have to be removed. Carefully check the parts for wear - this sprocket is marginal. The thin lock washer and locknut will be re-used

We’re going to describe the process of swapping old-style Sturmey hub internals for Sunrace-Sturmey parts. For the mechanically-minded, it’s all quite straightforward, and the only specialist tool required is a 16mm cone adjusting spanner. If you’re unsure about mechanical bits, contact Sturmey and Brompton specialist, Bicycle Workshop in west London (tel: 0207 229 4850).

Step one is to buy the necessary bits, and once again, unless your local cycle shop is particularly keen and knowledgeable, we recommend Bicycle Workshop.The hub gear internals will cost £70, and the indicator chain £4.50, plus postage, together with a labour cost of about £15 if the shop does the work for you.

Other parts may be needed though. Carefully inspect the inner and outer gear cables, gear shifter and Brompton cable guide. If the action of any parts is sticky or rough, replace ‘em! The same applies to the sprocket and chain. If they were fitted more than a thousand miles ago (always replace these parts together), you will also need a new 13 or 14-tooth sprocket and chain from a Brompton dealer.The new nickel-plated chain works perfectly well, but it must be 1/8″ and not the 3/32″ derailleur-type chain, fitted to the new 6-speed bikes.

Getting Started

brompton-5-speed-hub-upgrade-2

Removing the right-hand bearing cone. The next step is to unscrew the internals from the other end

You’ll need to remove the rear wheel, and as we delight in saying, if that proves tricky, this might be the stage to hand over to an expert.With the wheel off, thoroughly wire brush both the sprocket assembly and associated (right-hand) cone and locknuts. Repeat this operation for the opposite, left-hand bits and pieces too. It’s essential that grit doesn’t find its way into the hub, and you’ll be re-using these locknuts.

brompton-5-speed-hub-upgrade-3

Screw the new internal assembly into the shell and tighten. Note the old locknut and lock washer.

When the hub is reasonably clean, mount the wheel in a vice and remove the sprocket assembly, right-hand locknut and thin lock washer, putting the parts carefully aside in the order in which they were removed. Remount the wheel in the vice and remove the left-hand locknut and bearing cone.

You’re now ready to spin the internals out of the hub shell. If you don’t have the special ‘C’ spanner, and a hammer and punch fails to shift the ring, clamp the assembly in a vice and spin the wheel anti-clockwise.

brompton-5-speed-hub-upgrade-4

Final adjustment to the left-hand bearing using the cone spanner

With the old internals removed, carefully inspect the inside of the shell for foreign bodies, rust or signs of water damage. If all’s well the new unit can be screwed straight in and tightened with a hammer and punch. If not, the shell will have to be carefully degreased, cleaned and regreased – tedious, but very necessary.

You will now be in a position to screw on the left-hand bearing cone and the old thinner locknut. On the right (sprocket) side, carefully hold the bearing cone and spin off the right-hand locknut without disturbing the cone. If the adjustment is upset, the cone should be hand-tightened and backed off half a turn before being locked in place. Finally, put back the dust shield, spacer and sprocket, checking sure that the circlip beds down correctly in its slot.

…the most common cause of failure is misassembly following roadside repairs…

With the axle back in the vice, it’s time to adjust the bearings.The sprocket is an important part of the adjustment process, because the left cone should be tightened until (quoting Sturmey) there is ‘minimum’ free play at the wheel rim, but noticeable play at the sprocket, with no tightness or roughness. Lateral rocking of the sprocket looks alarming, but it’s quite normal.When satisfied with the adjustment, hold the cone nut steady and tighten the locknut. Don’t spend hours fiddling – it will need checking after a few weeks riding anyway.

The hub should now look exactly the same as the old one, but with a longer axle stub on the left-hand side.Again, this looks alarming, but it has no harmful effect. If you really want to, you can angle-grind this (very hard) axle back, but we wouldn’t recommend it.

Sturmey produced a special short axle hub for the Brompton, but the difference is merely cosmetic.The only other Brompton-specific parts are the thinner locknuts and right-hand washer that just enable the 5-speed hub to squeeze into the Brompton’s narrow frame drop-out.

brompton-5-speed-hub-upgrade-5

Assembly details. Note that the gear selector guide is followed by the lock washer and nut. The gear selector guide must point directly at the cable guide roller on the rear frame

It’s now time to refit the wheel to the bike, taking great care that the stepped anti- rotation washers sit comfortably in the drop-outs, and that the gear selector guide support (the washer with a funny bent bit sticking out), is followed by the lock washer and hub nut.The most common cause of 5-speed failures is misassembly following a roadside puncture repair, so do take care to get it right, or you could damage £75 worth of shiny new bits.The tab on the guide support is easily bent – it should stand at 90 degrees to the washer face – and the tab must point towards the cable guide roller assembly. If any of these parts are loose or poorly aligned, the gear cable will stick or wiggle around, causing missed gears. Finally, fit a new ‘blue’ ball- locking gear indicator rod, and refit the tensioner and chain.

Final adjustment

Adjustment is critical and needs to be carried out in second gear.You can either use a mirror to observe the blue band on the indicator rod, or very carefully turn the bike upside down, taking care not to move the gear shift.What you must never do is adjust the cable with the bike partially folded, which will give a completely false reading. In 2nd gear, the blue band should be entirely visible, but only just, if that makes any sense. As with the hub bearings, it’s a good idea to reset the adjuster after a few rides.

Upgrades with new parts can be unpredictable, but our conversion worked perfectly, and yours should too.With careful adjustment and maintenance, the revamped Sturmey hub should last for many years and revitalise a tired Brompton.

Bicycle Workshop tel 0207 229 4850 . Brompton tel 0208 323 8484