B
Blaze
Guest
OK, I have a new engineering project. My friend is motorizing his bike and he wants to have multiple gears. I have decided to try to make it into a 3-speed. We are starting with a diamond-frame 16 speed bike; 2 rings up front and 8 in the back.
It starts with standard installation of a grubee-type motor. Then I install an axle on the frame that moves the motor power to the right side. The motor power on the right side will now be using a bicycle chain. Basically, I will build a small axle with a standard motor sprocket on the left and a bicycle sprocket on the right, then attach it to the frame very close to the motor.
I will put the pedal chain on the inside ring of the pedals and the inside ring of the hub, and adjust the chain to be used without the derailleur. The pedals are now one-speed only.
I then choose 3 speeds for the outermost rings of the hub and leave the four in between those 3 and the innermost ring empty. The outermost 3 rings will be the 3 speeds used by the motor, using the stock derailleur to change gears. This creates a space between the motor chain and the pedal chain. The derailleur will be readjusted to limit movement to the outer 3 rings only.
That should do it. It's really just an easy, standard installation on a diamond-frame bike, until you get to the part where I move the motor power to the right side. The main project here will be fabrication of the axle to move the power to the other side.
Has this been done yet? Has anybody seen any photos that might help, or am I on my own here?
It starts with standard installation of a grubee-type motor. Then I install an axle on the frame that moves the motor power to the right side. The motor power on the right side will now be using a bicycle chain. Basically, I will build a small axle with a standard motor sprocket on the left and a bicycle sprocket on the right, then attach it to the frame very close to the motor.
I will put the pedal chain on the inside ring of the pedals and the inside ring of the hub, and adjust the chain to be used without the derailleur. The pedals are now one-speed only.
I then choose 3 speeds for the outermost rings of the hub and leave the four in between those 3 and the innermost ring empty. The outermost 3 rings will be the 3 speeds used by the motor, using the stock derailleur to change gears. This creates a space between the motor chain and the pedal chain. The derailleur will be readjusted to limit movement to the outer 3 rings only.
That should do it. It's really just an easy, standard installation on a diamond-frame bike, until you get to the part where I move the motor power to the right side. The main project here will be fabrication of the axle to move the power to the other side.
Has this been done yet? Has anybody seen any photos that might help, or am I on my own here?