E-bike conversions

[DamperMan]

I’m very keen to convert my old mountain bike into an e-bike.    There are loads of kits on eBay but I have no idea about there quality or usefulness.  I need to overcome the 15mph limiter for a start.  The plan is to use the main car less.     I’d like to be able to commute on the e-bike 25 miles each way and happy to charge though the day.  I’m sure I read some one on here was doing a conversion...  can I tap into your experience. 

[Mark (smokey mow)]

You won't "overcome" the 15mph limit unless you pedal hard and put the extra effort in yourself. Above 15.5mph it in the eyes of uk legislation stops being an EAPC and becomes a motorcycle.

https://www.gov.uk/electric-bike-rules

 

[Kevin Pullen]

Yep you can’t go over 250W for on road use, anything above that and if you get stopped you will get the book thrown at you, friend had a 1000W 48v brushless hub motor conversion got caught going over the 30mph limit 

got the book thrown at him, no tax no insurance not type approvedlost his license. Think local magistrates trying to make an example of him

[darve]

@Kit Car Electronics

[DamperMan]

I’m sure non of us ever break the speed limit in a car.   I see and understand the risk.  There’s always the ones who take things to far or do stuff in inappropriate ways like in a car.   I’m not looking for an electric motorcycle.    I average 18-20 mph on my road bike on the same commute. Just i’m Puffed out after and need a shower/ lowdown.  The ebike would be to supliment rather than replace these rides. I’ll be adding a good few watts myself.  up to 20 mph assistance would be nice.  

[Dave Eastwood (Gadgetman) - Club Chairman]

Surely the point that Banshee was making wasnt that it was just the equivalent of speeding - that was the minor issue; it was the equivalent of putting an unroad registered non-road legal car like an open wheeled single seater on the road and then speeding in that.

The book flying at you is because of the vehicle, not the speed!

[DamperMan]

I wonder how many of these Chinese conversions actually tick the boxes on the government requirements of being labelled correctly 

[Kit Car Electronics]

I've converted 2 bikes- one front hub motor, one rear. Both ridden responsibly and both capable of what you're looking for... Happy to share details on here

[DamperMan]

Cool... i’m Interested.   Naturally any greater than 250watts and 15mph is for private land off road use

[Kit Car Electronics]

Oh, and the 250W limit is unworkable and not consistent with the motor currents of even the certified bikes, so the speed limit is far more relevant. You can fit a speed limiter, of course.

[Arm]

Im interested in this one also

 

Ideally switchable so fully legal on road then off road full power.

[Kit Car Electronics]

The controller is the most important part of the conversion to make a compliant, switchable and great to ride bike. I have the V3 cycle analyst and it's absolutely brilliant.

[Kit Car Electronics]

@DamperMan and @Arm, if you post a picture of your bikes, I can give you some ideas of what parts you'd likely need to think about...

[Kit Car Electronics]

Here's mine - built for towing originally. It's a great feeling when an old bike gains a new lease of life:

For a front hub motor, you need strong forks as the dropouts aren't designed for the torque normally. You also need a good front brake. These are steel jump forks:

Here is the V3 CycleAnalyst controller - 20.5 miles in and still over half battery (36V, 15Ah Panasonic cells with a 20A speed controller)

2WD is surprisingly good in mud...

and here is the rear hub motor conversion I did for my wife's bike:

[Kingster]

4 minutes ago, Kit Car Electronics said:

Here's mine - built for towing originally:

For a front hub motor, you need strong forks as the dropouts aren't designed for the torque normally. You also need a good front brake. These are steel jump forks:

Here is the V3 CycleAnalyst controller - 20.5 miles in and still over half battery (36V, 15Ah Panasonic cells with a 20A speed controller)

2WD is surprisingly good in mud...

and here is the rear hub motor conversion I did for my wife's bike:

That takes me back! Manitou forks... always a tough call between them and Rock Shock Judy's in the early 90's

Still got my Marin Pine Mountain in the garage gathering dust...