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Julian Bond - 2014-03-01 07:36:41+0000 - Updated: 2014-03-01 07:36:41+0000

http://www.treehugger.com/bikes/shareroller-portable-turbo-kit-electrifies-any-bike-sharing-bicycle.html
https://www.kickstarter.com/projects/247419341/shareroller-first-portable-motor-for-share-bikes-a

Clip on, roller motor for the front tyre of a London BorisBike or similar.

Interesting idea. But I'm not at all sure how feasible it is. The design is for a 750W version, but would have to be 250W for the UK/EU market. The kickstarter page suggests the design people have done their research.

ShareRoller: Powerful portable turbo kit electrifies any share bike

Julian Bond - 2014-03-01 15:55:11+0000

Presumably with the charger that you've left at home or have in your backpack. Given the size and weight I really doubt the charger is built in.

Julian Bond - 2014-03-01 20:31:11+0000

Well there's quite a few people who've been playing with friction drives and I believe they can be made to work quite well. They're typically built with big RC outrunner motors with RC controllers and while these are amazingly light, they're not good when running at slow speeds. So one of the big challenges is to tailor the electronics to prevent everything blowing up when the user hits full power at 0-5mph.

See http://endless-sphere.com/forums/viewforum.php?f=28
http://endless-sphere.com/forums/viewtopic.php?f=28&t=53365
and associated embedded links