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Brompton Gear Range

Brompton Gear Range ‘Could the Brompton be ‘easily’ redesigned to take wider,more conventional hubs? The rear drop-out spacing is under 115mm,whereas ‘normal’ hubs are 135mm (with 145mm normal in the USA).As the Brompton folds to the right, the extra width might only be 10mm or so. Could the hinge be widened by 5mm? Are there […]

Hub Gear Conversion

If you think about it, the quality of a child’s bike is really important. If a child grows up with a heavy, impractical bicycle, he or she starts life with the impression that bicycles are heavy impractical machines.The evidence from the current generation is that apart from dabbling with BMX, the vast majority stop riding […]

Electric Bike Hybrid Transmission

The time-honoured bicycle drive system of pedal cranks, chain drive, and hub or derailleur gears has been in vogue for more than a century, and shows no sign of going away in the immediate future. But new thinking is starting to make an impact, and I am indebted to engineer Frank Moeller for his thoughts […]

Lower gears on a folder?

Lower gears on a folder?

“Could you tell us the options for putting very low (sub 30-inch) gears in a folding bike? Which folding bikes will accept a Rohloff hub gear? It’s very hilly around here.” Margaret Lunnon, Coulsdon, Surrey Alot depends on whether you are prepared to put up with a general lowering of the gears, or are hoping […]

Puncture-Resistant Tyres

No More Punctures, Please! “I have had three punctures on my Brompton since Christmas.The first in the front Marathon, the second in the rear Brompton tyre, prompting me to change it for a Marathon.The third was in the front Marathon again, causing me to regret spending on the rear tyre change. Just to make it […]

Small Tyre Design

The subject of tyre technology comes up rather frequently on these pages, mainly because their inherently higher rolling resistance tends to put small-wheelers at the cutting edge. In the mid-1990s, small tyres were at a considerable disadvantage against their bigger cousins in terms of rolling efficiency, but this was much reduced with the arrival of […]

Are trains really ‘green’?

“The current issue of Modern Railways magazine has an interesting article by Roger Ford on car, train and plane energy efficiency (June 2004, pp30-31). Ford’s analysis, ‘suggests, and I expect that this will generate some howls of protest, that a family of four going by car is about as environmentally friendly as you can get’. […]

Which bicycle brake system?

Which brake system? “A to B 41 was interesting, as always, but I’m a bit confused by Martin Fillan’s comment (Letters, A to B 40) about grease leaking onto brake drum linings and his suggestion about using a roller brake.What exactly is a roller brake? Is it better than a drum? And is it easier […]

Electric bikes – How Many Watts?

“There seems to be some confusion with regard to the legal power of electric bikes today. I am hearing that the maximum power permitted is now 250w and not 200w. Is this correct?” Alan D. Shaw Northampton Once upon a time, the law was the law and we all knew where we stood, but today […]

Methanol Fuelled Bikes?

Methanol Fuelled Bikes?

I ask these questions because it seems to me that a sensible use for bio-methanol would be as fuel for extremely low-mpg transport, such as 28cc engine-powered bicycles. Surely this would be a truly sustainable form of low cost transport and without the battery range limitations of electric bikes (speaking as a Heinzmann rider).” Simon […]

Recharging an Electric Bike on the Move

“Many years ago I cycled to Nice from home in the Birmingham area. Due to a road accident, I am not able to do such a silly thing again, though I would like to.Would it be possible and legal to tow a small generator behind an electric bike, leaving it running whilst riding?” Anthony Skidmore […]

Crank Length

I too used to belief firmly that 150mm cranks were only for kids, or adults with very short legs. In fact, after much experimentation, I came to the conclusion that extra-long 185mm cranks suited me best, and that the formula put forward by Kirby Palm [see www.nettally.com/palmk/crankset.html] was correct. Then two of my customers, Rob […]

Solar Rickshaw

“I was interested to see the solar electric recumbent in A to B 38. It occurred to me that if you could power a recumbent tricycle with two solar panels, one could probably power an electric rickshaw with three or four such panels?” Felicity Wright Redditch With the oil supply/demand crisis on the way, this […]

Solar-Powered Bicycle Lights?

“I think A to B should do a review of existing options for solar powered bicycle lights. I found one at www.energycapture.co.uk and the Alternative Energy Centre in Wales [www.cat.org.uk] sells a solar-powered 6 LED red emergency light which is sold with a bracket to attach to a bicycle.” Jonathan Pattison Leeds Clearly, in this […]

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 […]

Brompton 5-speed Upgrade

Brompton 5-speed Upgrade

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, […]

Avoiding Punctures

“Can you tell us how to deal with or prevent punctures? I don’t mean sticking a patch on, but what is the best strategy? I believe that the hassle of punctures really does put people off using a bike regularly for important journeys. In Peterborough the cycleways are edged with thorn bushes like pyracantha.” James […]

Bicycle Brake Lights

I’ve been trying to locate a rear LED light incorporating a brake light.The only ones I have seen recently are those gimmicky types with built-in indicator lights. I’ve managed to find a few products on the internet, such as Mavic, whose ML-273EZ seems to fit the bill. Gethin Sheppard Cowbridge, South Glamorgan The Mavic design […]

Solar Powered Bicycle – The Results

Solar Power Results Readers may recall the launch of my solar vehicle experiments in the last issue. At the time – having made a number of purely theoretical calculations – I concluded that a 20 watt solar panel might just be viable on an electric bicycle. In the event, for reasons of panel size and […]

Solar Powered Transport

“I’ve always been interested in the idea of solar-powered transport, but no-one seems to have built anything practical yet. Is a solar vehicle a practical proposition in the UK?” Jonathon Crouch King’s Lynn Professor Pivot replies: Clean inexhaustible solar power has been a transport dream since photovoltaic cells first began converting light directly into electricity, […]