Handbike question

[FST4RD]

Why do handbikes have the cranks in the same position on both sides rather then opposite to each other like on a regular bike?
I thought it would be much easier on the body if the cranks were opposite, plus it would give you more power as you can push and pull at the same time?

I am assuming that since all handbikes I have ever seen have the cranks in the same position that there is a good reason for it?

 

[cyfa2809]

Similar to why you'd row dual handed i guess.

 

[Raging_Bulls]

also, the arms are used both to pedal and steer. If you put them like on a bicycle, you'd be making a small left and a right turn on every revolution, losing lots of energy.

 

[cyfa2809]

I did think side at a time for some but i assume thats casual rowing and not like olympic or similar which i pictured?


Thats a pretty extreme bit of kit.

 

[FST4RD]

I had these visions of racing yachets and those rigging things that they wind that have cranks and hand holds (I don't know the technical term).
I can see what you mean though guys, never thought about it like that so much.
It just looks awkard how you have to lunge forward everytime you pedal. Must be hard trying to climb a hill like that?

 

[cyfa2809]

Wheelchair user tend to use both wheels at once and the 'lunge' is almost the same just a different orientation.
Adaptation.

 

[rosstheboss]

It's probably something to do with rotational force - when we walk or run, the force is transferred across our body and so our opposite arm moves, not just for balance but to counteract the force of moving the leg. Hence why sprinters are stacked - they have to be able to move their arms as fast as their legs, likewise, the faster they can move their arms the faster and more efficiently they can move their legs. So if you were using a normal cycling crank, your lower body would be wiggling all over the place....

 

[velomaniac]

Also to do with steering if its a fork mounted drive wheel. It'd get unsettling to pedal and steer into a corner without your hands both in the same plane at any given time.

 

[legrandefromage]

Ask danson67 - he builds them:

http://www.draftwheelchairs.com/