On-Wheel Electric Conversion Kits

Electrically assisted bikes, trikes, etc.
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Joined: 15 May 2020, 8:12am

On-Wheel Electric Conversion Kits

Postby davidmills » 15 May 2020, 8:20am

Hi All,

I am looking for an electric conversion kit and I like the look of these which attach to your frame and have an external wheel to drive your rear wheel:



What I really like about them is how small and compact they are, and how they appear like they will be relatively easy to install / remove and how the bike can be used in normal or electric mode. My only issue with these however is the price (if they had been cheaper I would have already bought one). I am looking to use this to assist on a commute so I do not arrive to work sweaty, and on the odd long ride just to help me up a hill or 2.

Does anyone know of a similar style of electric conversion kit which is more affordable?

And does anyone have any experience of these type of conversion kits who could recommend them or warn against them?

Many thank!

EDIT: I should have mentioned that the bike I am looking to convert is a road bike.
Last edited by davidmills on 15 May 2020, 11:20am, edited 1 time in total.

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Re: On-Wheel Electric Conversion Kits

Postby Graham » 15 May 2020, 8:29am

Driving the wheel through the tyre will increase the tyre wear by some unknown - but non-trivial amount.

If the pressure between the drive and the tyre is light - I would expect it to suffer from slippage especially when wet. But at least it shouldn't gobble-up the tyres too quickly.

If the pressure between the drive and tyre is heavy - Less prone to slippage, but greater tyre wear.

If you do buy one, please come back here and tell us how it goes. Thanks.

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Re: On-Wheel Electric Conversion Kits

Postby stodd » 15 May 2020, 9:23am

Tyre wear will be an issue as mentioned. Also I think they are less efficient than regular hub or crank motors (not sure by how much).
The first of your references has a very small capacity battery (192wh).
The second emphasizes the battery is a trendy design, you have to dig deeper to find it's a choice of minuscule 160wh or small 200wh.

Range on either is likely to be very limited. To get an idea use https://www.bosch-ebike.com/en/service/range-assistant/ and put in your bicycle and riding conditions, then halve the results (results by default are for 400wh battery) and take of a bit more for inefficiency, or a lot more for the 160wh battery. Even though that is for a different system it should give an idea. Could be a good option on a fast bike if you don't plan to use it at all on the level (where you may well be riding above the legal 15.5 mph assist limit anyway), just as a booster on hills.

For more detailed advice post at https://www.pedelecs.co.uk/forum/forums ... ussion.42/

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Location: West Sussex

Re: On-Wheel Electric Conversion Kits

Postby hemo » 15 May 2020, 11:26am

I have a friction drive a UK designed and built Revos, using a small nobbled treaded tyre the centre gets chewed up at an alarming rate until nearly smooth. It's a simple design but the motor is a bit noisy as it is brushed and not signwave , downside is most can't be detached simply from driving the wheel so is constantly rubbing. Lightweight mine only adds 2kg to the bike, the Revos is all weather rideable with out traction loss. The Revos is a simple fit, bottle battery/cradle to the bottle fixings, rear small friction drive and a led sensor on the chain stay that picks up a signal by the gears teeth. Back pedal half a turn to turn off the drive and a gain back pedal half a turn to engage the drive again.
My one is ok but find the sensor on the chain stay does moves so doesn't always pick up drive as it misaligns with teeth pick up, realignment is needed sometimes.