Mechanical Engineering Tech Student
Hi my name is Lee and I am a Student in Edmonton Alberta, Canada
I am currently working on a final project for my program and am wondering if i could get some help from the people in this comminuty.
I am designing an add-on for a Wheelchair which involes using a bicycle shaft drive and internal gear hub for a person to pedal with their arms to move around. I understand the basics of how the bicycle shaft drive works but google doesnt help for more advanced questions.
I need to know if a shaft drive system can be used to move backwards?
What the cheapest internal gear hub that is modified to work with a shaft drive system? so far I could only find shimano alfine but it is out of the design price criteria.
And I am most likely going to design my own shaft as the length needs to be increased. But i need to know who makes the cheapest shaft as well?
If anyone who sees this knows anything about this or can point me to someone who can I will be forever grateful.
Bicycle Repair Man !!!
We have an adaptive cycling program through the Bicycle Commuter's Society and consult on these projects and also have a bicycle fabrication shop here in Edmonton... if you are at NAIT then we aren't that far apart either.
Most adaptive bicycles that rely on arm power still utilize a chain / derailleur system to reduce weight and to simplify the system... most wheelchairs are not designed to operate at great speed so what you are looking at more is building a hand trike and these are available and there is a good number of people using them in the city now.
Endangered Serotta Rider
Welcome to biekforums!
It depends, if you have a freewheel on the hub you will not be able to move backwards via what you're using to input effort. However you can coast.
Originally Posted by MechEngTech
If you opt for a "fixed/ track" set up where the gears for the shaft are built into/ bolted directly on the hub body, then you can go backwards via applying opposite input effort. However with the latter, you cannot coast. But you get the traditional wheelchair drivetrain.