MrCharlie

Hey folks. I'm a long-time cycling obsessive with past experience working as a mechanic and performing fits. Nextdoor to me is a 6 year old paraplegic boy who recently received a recumbent handcycle--a loaner-- from a local organization. I've taken it upon myself to take care of any mechanical work needed and also to get him comfortable riding.

I am wondering if there are any resources on fitting such a bike. My guess is that he is on an adult cycle, and before I start adjusting, I'd like to get the basic principles of fitting a hand cycle.

Foremost on my mond is crank length. The bike has 175mm arms, which seem ridiculously long. At present, he is having to lean very far forward to complete the motion. Almost like he's towing. I can't imagine that this is biomechanically ideal. I know that, using my old shop connections, I can source some reasonably priced arms as short as 140mm, but I don't want to overshoot--undershoot, I guess in this case.

v2505

you can overcome crank length with gear ratio or vice versa. there are many ways to do it. most basic thing is comfort and ease of use. i have no actual experience, other than anecdotal, and i just built a bike and created the 'cockpit' so he had room to rock back and forth during the stroke. he was too small for his first bike and developed a rhythmic pedal stroke with a ton of power by having the ability to use his body. That may not be an option for everyone though.

RonInBC

Any update on any mods that you did?

Yes, pedaling a hand crank bike is a different experience. The one's that I've either built or ridden impart a pronounced forward and backwards action and I felt that my abs were getting a workout. Don't think that was a bad thing though.

Ron