DCBIKEFOROSAZE

Greetings to all:

I am interested in buying, building or modify a bike for my 2 1/2 year old son who has spinal muscular atrophy. At this point I just want something he can sit on with some upper body support (chair type) and for him to pedal with very low resistance.

Longer term I want sensors in the pedals to detect level of effort and relay the detected effort to a small motor to assist with propulsion.

My son is intellectually fully functional. He has weak legs, trunk and arms. He is being provided physical and occupational therapy. We are encouraged to keep him active without exhausting him.

Thanks,

DC

Doug5150

The Bionx electric assist operates exactly this way, activated by pedaling exertion (by measuring chain tension): https://www.bionx.ca/en/main/default/1.shtml
Note that it has a 20" wheel as an option.
The Bionx normally has a 20-mph top speed; for such a young child you might contact Bionx and explain the situation and there may be a way to program in a lower speed-limit to the assist (-I know that the 20-mph upper limit is programmed in, and can be bypassed with a special code).
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The bike is another whole problem, not a lot of bikes around for children that young that use a 20" rear wheel. There's also an 18" wheel option, but I know even fewer bikes that use it.

Greenspeed isn't cheap, but has done some custom child's trikes in the past: https://www.greenspeed.com.au/

Alternately, you could look into obtaining a KMX trike and modifying it for the rider's smaller size (shorter pedal boom and seat): https://www.kmxkarts.co.uk/index.html
The KMX already comes with a 20" rear wheel. (NOTE--there are no US dealers for the KMX trikes, so you'd have to order from UK/Europe to get them)

This page shows some kid-sized recumbents, some of which are trikes. Many are homebuilts, but some are commercially-made examples you might be able to track down and use.
https://mnhpva.org/Mini_Bents/Mini.html

Good luck.
~

deputyjones

I think the founders of the Stoke Monkey product post here. Maybe they would be willing to assist you?

https://cleverchimp.com/

Rev.Chuck

This is not an assist bike but would be an inexspensive start

https://www.trailmate.com/productBananaPeel.cfm