Any limitations on kit options for this donor bike ?

[eddieo]

If you are loosing money because you don't have a suitable bike why not get a moped to get you to clients, much cheaper then a car........you can still have a e bike down there for leisure.

It really is a case of horses for courses,....some e bike will do it but will probably have to be illegal to make the journey comfortable. After all time is money. A Bosch bike with 400 ah battery will do it, but a moped faster....with the fast charger (1.5 hrs - 90%) really makes a difference and sets it apart from most yawn inducing chargers...

 

[BAH48]

Some while ago I said " forget ebikes and buy a scooter". After reading about your situation I haven't changed my opinion - you can buy a new 50cc scooter for about £500.

 

[103Alex1]

Some while ago I said " forget ebikes and buy a scooter". After reading about your situation I haven't changed my opinion - you can buy a new 50cc scooter for about £500.

I understand what you are saying. Not an option.

 

[BAH48]

OK, I can only see one option, buy a 500w rear motor from BMS with a 36v 20ah battery - fitting should be within your capabilities, if in doubt, ask and take photos before you do anything. You will get the range if you are prepared to use a lot of your own energy - be very light on the throttle. You will have the power to climb the hills and more or less achieve the results that you want. I can't see that you can loose much as you would be able to sell on the motor and battery if it didn't work for you.

 

[Old_Dave]

with a 36v 20ah battery

Or suffer the slings and arrows of outrageous fortune and make the bird fly by going down the lipo path

 

[eddieo]

Ezee kit with big battery and get John to fit or arrange fitting..UK support that way

 

[103Alex1]

OK, I can only see one option, buy a 500w rear motor from BMS with a 36v 20ah battery

I think this is the most viable option, both in terms of cost and performance. The combination does have a slightly higher effective top assist speed too that is much closer to the speeds I normally ride at anyway - suffice to say it would simply allow me to sustain speeds I can ride at unassisted on the flat over moderate inclines too. All roads are pointing here.

I've no problem pedalling - if the motors had been capable I'd have preferred a crank drive, but it's not going to work when I take on the steep gradients with what you can get as a kit for an affordable price. You're into £3k-£4k territory built, don't have the battery capacity for any sensible range so even then wind up making huge compromises. £500 for the bits sounds far less of a gamble all in all. Even if I hammered a battery completely in a year (unlikely as not there all the time), the cost would only be £250 for a replacement. I can live with that.

I can't see that you can loose much as you would be able to sell on the motor and battery if it didn't work for you.

Indeed. Someone might even like the whole bike but I doubt I'd be willing to part with it ! I'm intending to convert a Trek8500 MTB which although well used on trail has a lovely silver lightweight frame in decent used condition, XT, 9-speed cassette (27 gears) and hydraulic disc brakes which are extremely effective. I blew my budget just getting the donor bike but couldn't resist it... these were £1600-1800 when new eek.

 

[eddieo]

With your weight and fitness a deristricted 250 watt bike more then powerful enough, why risk anything, I dont see the point. Mine does 20+mph and I'm 17 stone and far from fit. welcome to try it if you want, maybe some other members can demo theirs. All theory and no practical experimenting a bit of a waste of time..

 

[BAH48]

There has to be a leap of faith, you'll only know when you either build it or buy it and use it regularly.

 

[103Alex1]

I guess a derestricted 250W is pretty much same deal as a 500W and just as 'naughty' ? .. plus it's best part of £900 for a kit from these guys against a top budget of £550 now, having paid a lot for the donor bike. The £350 saved is half a decent 2nd hand carbon Ultegra road bike which I'd like to buy when I've saved the funds for it (and won't be going to be left in Devon !!).

I'm more interested in sustained hill climbing at an average speed rather than top speed on the flat - 22mph on the flat is plenty. For higher speed riding on flattish ground would rather use a lightweight road bike than an eBike, but hills are too severe in Devon for me to really enjoy riding one - plus you can't carry anything with you to speak of so it's too limiting for multi-use down there. I'll keep my very high speed riding to the plains ... without a motor .

Cumulative cost of testing bikes / kits going via public transport round Britain is now so high I decided to save my pennies and just take a punt on the most likely affordable solution. If it's no good then it gets sold on.

 

[eddieo]

Alex in box full


I dont see it like that, as one is a blatant disregard for the law, the other could be (pathetically I admit) argued as a mistake while fixing it, fault with controller whatever.....I know which position I would prefer to be in.

 

[103Alex1]

Oops - thanks. Cleared a bit of space !

 

[BAH48]

Alex,
My requirements are similar to yours, for different reasons and I have come to the conclusion that either a Bosch crank drive or 500w hubmotor will work. A 250w motor might work with more volts/amps but I would only know by trying it. It's not a 250w motor then so what is the point? A 500w motor can just as easily have a 250W output and be within the limit. The crank drive motors have a 500w output when needed so - as we all know, it's all a can of worms

 

[eddieo]

Bosch has a 700 watt peak and why it climbs so well..hardly a can of worms as it cuts out at 15.5 mph. to use this peak as justification to use a blatantly illegal motor laughable to be honest....

but I dont think the Bosch suitable for a very long commute unless very fit, and if fit use a road bike as it will leave most e bikes standing

 

[103Alex1]

Bosch has a 700 watt peak and why it climbs so well..hardly a can of worms as it cuts out at 15.5 mph. to use this peak as justification to use a blatantly illegal motor laughable to be honest....

but I dont think the Bosch suitable for a very long commute unless very fit, and if fit use a road bike as it will leave most e bikes standing

The Bosch is not road legal in UK as has been extensively debated in other threads. Using it contravenes the Road Traffic Act, pure and simple. You can restrict a 500W rated to legal speed too but as you say can of worms. I've no interest in riding at 28mph unless on a downhill, unassisted with very good visibility. Bosch won't hill climb consistently over long distances any more than any other motor with a high 'peak' but low continuous. The 'peak' rarely lasts long and after that power sags back.

The higher power rated motors (suitably coupled) if operated within legal speeds are only a problem if you use excessive acceleration on the flat that is dangerous for the conditions. Legalities aside, that's down to rider being responsible.

I agree 100% on the road bike for long commutes if there are no challenging terrain issues to overcome and you are reasonably fit. It is unfortunately the potential abuse of the higher continuous output motors which cause them to be restricted and that (as usual) means people who actually need them for a specific perfectly safe purpose become subject to same. Such is life !

 

[BAH48]

eddieo,

I think that you have just reinforced my point, an apparantly legal ebike can have an output of more than 250w, so a 500w motor can be just as legal if most of the time it's used at 250w and restricted to 25kph.

 

[eddieo]

the EU law is clear, a 250 watt motor

 

[Old_Dave]

Is that "clear" as in clear as mud Eddie ?


Sent from my iPhone using Tapatalk

 

[BAH48]

"the EU law is clear 250 watt"


Of course it is - what am I thinking of?

 

[Jeremy]

the EU law is clear 250 watt

Well, actually it isn't. You are allowed far more than 250W under the definition in the EU regulation, which is why quite a few newer ebikes are more powerful than they used to be.

We've discussed this at length already, but it's perfectly possible to have an ebike that delivers 500W or more, yet is rated as 250W using the EU power assessment method.