We’ve talked about the evolutionary aspects of electric bicycle development before. And, love ‘em or loath ‘em, the early years of this new century provide a fascinating opportunity to observe transport evolution in progress. Broadly speaking, electric bikes have split into two groups; the heavy Chinese bruisers, personified by the Powabyke, and the newer gazelles of the genre – light, agile pedelecs, such as Giant’s Lafree.
This month, we’re riding the Ezee Forza, a fascinating hybrid from a small Chinese company that might turn out to be an evolutionary dead end, but might also herald the demise of the 40kg dinosaurs. Manufactured in Shanghai, it’s relatively cheap, but it also offers much of the sophistication and performance previously found only on the most expensive machines.The result is something quite new: decent equipment, light alloy frame, NiMH battery and hub gears borrowed from the Lafree concept, but with a down- to-earth Powabyke-style front hub motor and a potential price tag of around £650.That would put the bike head-to-head with the mid-range Powabyke, but with weight and performance closer to the gazelle evolutionary strand.
The Forza has an alloy frame and upright riding position broadly reminiscent of the European-designed Giant Lafree.There’s even a similar characteristically curved frame tube, but unlike the Lafree, the tube curves down towards the wheel. Another difference is the slightly garish polished alloy frame, against the Lafree’s understated enamelled version, and some humungous chunky welds, where the Lafree looks delicately crafted.
…not the lightest on the market, but close, and it offers a lot more performance…
Without the battery, the Forza weighs an acceptable 23.6kg (52lb), putting it mid way between the Powabyke Commuter (27.6kg) and the relatively sylph-like Lafree Twist (18.3kg). But unlike either of these machines, the Forza offers suspension – well, suspension forks and a bouncy seat pillar anyway – so it should really be compared with the Lafree Comfort, which weighs 21.4kg without battery.There’s only a couple of kilogrammes in it, so we’re obviously looking at a fairly skillful weight honing job.
Factor in the battery and the Powabyke weighs close to 40kg, the Forza 29.4kg, and the Lafree Comfort 25.3kg.The Forza isn’t the lightest on the market, but it’s close, and it offers a lot more performance, as we shall see.
Typical of Far Eastern electric bikes aimed at Germany and the USA, the Forza has a saddle as broad and flat as a dinner plate, with modest height adjustment of 86-89cm, even before the suspension post has sagged under those decadent western buttocks.We did manage to twiddle the saddle up to 96cm by ignoring the ‘max’ warning, but for those lucky enough to sport a slimline Euro-bot, and lovely long legs, this sort of thing is a bit of a joke. It will also more or less guarantee knee damage, should you put any great effort into the pedals. Forza tell us that production versions will come in two frame sizes.
The suspension forks and seatpost are not of the best quality, but they do a manful job, coping with most road conditions. Actually, a fair bit of the resilience seems to come from the chunky 26″ x 1.95″ Kenda tyres, which are knobbly on the edges and smooth in the middle, in true ‘mountain-style’.The bike would go further and faster with narrow high pressure tyres, but it might not be so comfortable.
Brakes are a bit of a mixture – V-brakes at the front and Nexus roller brake at the rear. Under perfect conditions, the brakes are well matched, achieving brake force of .75G (front) and .35G (rear). Our concern is that these two very different systems would react differently to wet or icy conditions – something to watch.
Under way without power, the three-speed Nexus hub feels somewhat over-geared at 46″, 62″ and 85″, but with the motor engaged, the ratios are about right. Noise levels are low by hub motor standards – much quieter than the Powabyke, but a little noisier than more expensive designs, such as the Heinzmann.
Thanks to the confusion over the legality of throttle-controlled electric bikes in the UK, Ezee provided us with a bike that could be used in either pedelec (ie, only when pedalling) or full throttle-controlled electric mode.We should also point out that our bike is very much a prototype, and final control specification has yet to be decided.
The pedelec mode proved most unsatisfactory, switching straight to full power after a second or two, and staying there for a while after you stop pedalling.The brakes are fitted with over-ride switches to cut the power, but in practice, this sort of thing is useless in heavy traffic and can take you dangerously unawares during a tight U-turn, for example.
In throttle mode, the bike proved much more controllable, although once the rear- mounted key is turned to the ‘on’ position, there’s no safety cut-out, so inadvertent use of the throttle will set the front wheel spinning.This should be sorted on production bikes, so it would be unfair to dwell too long on this.
Safety grumbles aside, once you’re on the move, the throttle gives a nice progressive response and the motor pulls cleanly from a stand without fuss, getting into its stride from around 8mph, and proceeding with some enthusiasm to 16mph, or as much as 18mph with a fresh battery.
Er, isn’t that illegal? Well, yes and no.When 90% of motorists choose to pass our 30mph-zoned gate at 40mph+ and the police have no intention of stopping them, we’re not going to criticise an electric bicycle doing a modest 18mph are we? Unfortunately, Ezee tell us production machines destined for Europe will incorporate a 15mph speed limiter. Perhaps the EC would like to do the same for cars?
The front hub motor is compact, economical and powerful, and the NiMH battery – although tiny by Powabyke standards – offers an impressive 324 watt/hour capacity in a particularly lightweight package.This battery/motor combination results in a cracking top speed, plenty of mid- range torque, and considerable endurance. We completed our 17.6-mile ‘mountain’ course in a record-breaking time of one hour seven minutes, thanks to some superb hill climbs, including a long 12.5% (1 in 8) stretch, cleared at a steady 9mph.The biggest problem with a powerful motor is holding it back, particularly on a bike with only three gears – the technique is to use full throttle until the bike begins to slow, then change down to second and throttle back until you crest the ridge. On full power, the motor will try to storm the hill at a ‘late for work’ pace and the battery will suffer.The problem with hub motors (as opposed to crank-driven systems) is that on really steep hills the motor is working more slowly (and less efficiently) than it would like, so a good general tip is to engage first gear, throttle back further still, and do a little more work yourself.The practical limit in this case is about 17% (1 in 6).
…only two come close…the Powabyke Commuter and the Dawes S-Drive…
Having reached our destination without the slightest hiccup or falter, we turned straight round after a nice cup of tea (thanks gran) and did it all again in reverse. Average speed continued to hover around the 15mph mark (yes, that’s the legal maximum for power assistance), until 26 miles, when the first of two low fuel warning lights popped on during a steep hill climb.The indicator has three lights – green, yellow and red, but green stays cheerfully illuminated until the battery is almost exhausted and red never makes an appearance. By 31 miles the yellow light was permanently on, and the end came quite suddenly at 32.8 miles, covered at a cracking average of 14.8mph with excellent fuel consumption of 9.9Wh per mile. Battery replacement will probably cost in the region of £200, giving an estimated running cost (note, we now include 2p per mile for cycle consumables) of 5.8p per mile.
…the Forza is in a class of its own in terms of speed, range and rideability…
How do the figures compare? Running costs are amongst the cheapest we’ve seen, and about the same as the Powabyke. In terms of range, most electric bikes can scrape up to twenty miles these days, but only two come close to the Forza – the Powabyke Commuter did the same mileage at a slightly lower 14.3mph average, while the long-range version of the Dawes S-Drive (now discontinued) managed 48.9 miles, but at a rather lethargic 13.4mph.
In motor-only mode, the Forza managed a shade under 20 miles on a flattish circuit – about the same as the Powabyke again, and exactly as claimed (35km). If you don’t think that’s remarkable, remember that the Powabyke has a monster 13.4kg battery, but the Ezee battery weighs just 5.8kg… And the average speed (on a wet and blustery spring day) was a consistent 15.5mph for most of those 21 miles, falling to 12mph or so on modest hills and 9mph on a 10% gradient.When the battery eventually expires, the Forza is surprisingly easy to pedal, thanks to a much more rigid frame than the Lafree. Standing out of the pedals is easy on this bike, which is fortunate, because you’ll be doing plenty of it with a 46″ bottom gear. Ezee tell us that production bikes will have the Nexus 7-speed hub as an option – worthwhile if you expect to tackle hills unassisted. But even in three- speed form, the Forza is in a class of its own in terms of speed, range and rideability.
With a 324Wh battery, charging is never going to be quick, but the large battery has been paired with a powerful charger – a neat little fan-cooled unit measuring 19cm x 10cm x 5cm and weighing 1.1kg (half of this in the generous three-metre leads). A 90% charge takes exactly five hours, after which the charger reverts to a low top- up rate till morning. Fast chargers can be inefficient, and this one manages only 50% efficiency, so the process generates quite a lot of heat, consuming 600Wh over the five hours (and 16 watts per hour thereafter). Chargers of this kind should not be left connected for too long – we would suggest a maximum of 15 hours.
Possibly the broadest package of any we’ve tried, although not necessarily the best componentry.The Forza has a useful rear rack complete with traditional spring-thingey, chainguard, substantial but not overly heavy centre stand, basic but acceptable trip computer and a dynamo lighting set.
The trip computer works well enough, but if you push the buttons in the wrong order it’s possible to erase everything, which is a bit annoying. It’s also a bit short on functions, offering only speed, elapsed time and mileage, but no average calculation, which looks a bit mean. On the other hand, it’s simple to use and easy to read, and it’s the first standard trip computer we’ve tested, so top marks.
The dynamo lighting system is based on rather crude copies of European products – a shaky-looking bottle dynamo, a neat but remarkably ineffective front lamp, and a workable, but old- tech rear lamp.The dynamo slips and whines for a mile or so until it warms up (and fitfully thereafter), the lamp bulbs look and perform twenty years pre- halogen, and the wiring looks vulnerable at the rear, but it all works, and it’s part of the package.
Our prototype Forza has one or two minor niggles, such as a noisy rear mudguard, and some glaring faults in the control software, but everything else performed well, from the fast compact charger to the lightweight battery and quiet efficient motor.
Weight – both of the battery and the bike – is particularly low, resulting in reasonable economy and sprightly performance.We’re quite convinced that with a few tweaks, the Forza could be a very effective machine indeed.
Should the big manufacturers be worried? If the Forza can sell for less than £700 in the UK, Giant will be under some pressure, but the sheer quality of the Lafree will probably keep it in the top spot. For Powabyke on the other hand, machines as good as this could mark the end of the line.The Forza is (much) lighter and will probably be cheaper. It also looks better, and it offers an impressive list of accessories, from lighting to suspension. Cost, performance and range are about the same, but the Forza recharges in almost a third of the time.Which would you buy?
Ezee Forza £650
Weight Bicycle 23.6kg (52lb) Battery 5.8kg (12.8lb) Total 29.4kg (64.7lb)
Gears Shimano Nexus 3-speed hub
Ratios 46″ 62″ 85″
Batteries Nickel Metal-Hydride
Capacity 324Wh Max. Range Pedelec 32.8 miles Motor-only 19.9 miles
90% charge 5 hours
Fuel consumption Pedelec 9.9 Wh/mile Motor-only 16.3Wh/mile
Running costs 5.8p per mile
Manufacturer (no UK distributor yet) Shanghai eZee Kinetic Technology mail firstname.lastname@example.org web www.ezeebike.com fax +86 21 58224040