GSB's electric Felt Hardtail

Well screwed together and finished that! My dad bought an existing conversion off Ebay, a low-mid range Giant MTB IIRC, heavy and a massive frame, a Front wheel motor so effectively 2WD if he pedals. He's tidied up the previous wiring and containers. Hope the batteries were good quality.
 
2WD would be useful in muddy slipery conditions!

Keep an eye on the dropouts with wheel motors. Especially front dropouts on front driven bikes. The dropouts are not built to take torque directly applied to them, and there are many many many broken teeth and faceplants due to the motors twisting themselves out of the forks. Torque reaction arms are a must, and soild steel forks are preferable... It also goes without saying that the headet gets a hiding from such a system, so keep an eye on that too.

Batteries are always the weak point, they need to be well looked after, all the cells balanced, and depending upon the type, may only last a couple of years anyway.

They also tend to be very expensive, are very easy to break by taking to much out of them, and really dont like being dropped very much. That's especially true for Lithium Polymer (LiPo) cells which tend to catch fire if they are dropped, punctured, shorted, undervolted, overcharged, or looked at in a funny way. They offer the best punch for an ebike though since they have extraordinaily high power density per kg, so many aftermarket kits have them. Personally, I wouldnt have them in the house...
 
Thanks GSB, Those are great tips and warnings. It's a leisure bike to go with his general stuff, an experienced motorbiker and once mechanic too though I really don't know what he knows about cycle bikes. Will mention this next time I drop in. the 2WD thing seemed interesting though, a front and rear hub motor might be fun for hilh climbs in general or in slop or snow! :D
 
GSB":19gb7cuh said:
Power delivery in legal mode is a peak 250watts of assistance...

You may want to take a closer look here - https://www.gov.uk/electric-bike-rules

The chances of getting collared are remote, but if you do get caught your driving licence will be left in tatters, not to mention the fines. Unlicensed vehicle, no road tax or insurance, wrong helmet etc...
 
Oh, I've read it, and countless other resources too. The fact is, no one really knows what's going on at present, since the law is in flux and the lawmakers have had bigger fish to fry. European directives, that are supposed to replace our old electric vehicle rules, say 250watts rated power and no independent throttle. No type approval required. British Law says 200watts, but a throttle is allowed. Every ebike in Halfords is Euro law compliant, not british law compliant. It's all very-very confused.

It's also "rated" power, and any electrician will tell you rated and actual power are two very different things. A 250w rated motor can output far more for short periods, such as when the battery is fully charged.

I've played it safe, or at least as safe as I can for the time being, by limiting my motor to a constant measured (not just rated) 250watts of input power when on road, and it only works when you pedal it. It's very conservative in its legal mode, and considerably slower than the ebike you'll buy from Halfords. As an additional safeguard, I don't often ride on roads. I hate riding on roads, and prefer to stick to muddier locations where possible.

It's all so utterly confused that to date there has never been a successful prosecution, although I do know of one that came close. The driver of an electrically powered pedicab in the west end was stopped and ultimately charged with having an overwieght machine, which I think then came to nothing anyway since the European law has no such wieght limits. Bear in mind that's for a type of vehicle that is being actively targeted by police in London, and they still couldn't make it stick for lack of any real case law.

Since there's such enormous confusion the DfT have stated that no one with a technically illegal euro power bike will be prosecuted, and have now started consulting on just what the law should be. They launched the consultation yesterday...

https://www.gov.uk/government/uploads/s ... cument.pdf

I imagine that in some way, somehow, my bike is illegal. Yet nic one is able to tell me how that might be. I even took it along to show the local police at a bike show, and see what they made of it. They're not really sure...

When building it I went to considerable lengths to ensure it would not exceed any of the specifics in law. I rarely ride on road anyway, and I certainly don't ride it at silly power mode on the road. In fact I rarely engage the dafter power levels when off road, unless climbing a very big hill, or if I have a spare chain and chain tool with me. I really don't relish pushing the bloody thing home again if I break it, since it's not the sort of bike you can throw over your shoulder anymore.
 
Re:

This is crazy, but also cool, it makes a lot of sense in many ways, I can't wait for 5 or 10 years down the line when batteries may have got a lot smaller and lighter :D

thanks for posting this.
 
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