Building my first motorized bike

Discussion in 'General Questions' started by Coltonhursey, Aug 1, 2013.

  1. Coltonhursey

    Coltonhursey New Member

    So, I'm kinda new to this whole motorized bike thing. I'm used to being under the hood of a car. But lately I have been riding a bicycle a lot, and working on these small engines a lot, and they seem like they are just meant to be together.
    I have a lot of mechanical experience, working on cars, I don't go to mechanics, never have. I do everything from changing my oil to rebuilding and changing my motor. I work at a factory doing industrial maintenance, and recently, I've began working on bikes and small engines.
    Enough about me, more about my project/questions.
    So, I'm using a shimano mountain bike, with 24in wheels, and I planned on using one of the 41t cassettes with it. I think I will be removing the pedals, and mounting the motor to the frame like a motorcycle motor. It's a poulan 25cc 2stroke in pretty much new condition.

    Now, here's the problem I'm running into, I want to use a centrifugal clutch from a gocart, but those use 3/4 in shafts that are keyed. My Weedeater uses a 3/8 in shaft with a square slot through it long ways.
    I have tried finding a solution for this, and researching any information, but I keep running into dead ends. I have though about using a trimmer clutch, but it's a direct drive trimmer that I pulled the motor from, and if I have to buy a clutch, why not buy one that is made for a small vehical?
    does anyone know a solution for this problem?