I would like to build a motorized mountain bike

Discussion in 'Introduce Yourself' started by mtbike, May 16, 2010.

  1. mtbike

    mtbike New Member

    hello, so i want to build a motorized mountain bicycle that could be used both in the woods (trails) and on the side of the road, i am more interested in the speed that this bike will reach..any suggestions where to buy a good quality motor kit? also do they sell motors that are more than 80 cc that can still be mounted on a bike?

  2. GearNut

    GearNut Active Member

    Welcome to the forum!
    If you want trail riding torque and fast top speed, you'll need gears.
    You can mount darned near any engine in a bicycle frame. Some folks use lawn mower engines or small motorcycle/ scooter engines. The real question is whether the simple bicycle frame used can reliably handle the power and weight applied to it.
    There are lots of issues to be aware of when going to a big engine.
    Surf around this site, most of your answers are in here all ready.
    Have fun!
  3. wheelbender6

    wheelbender6 Well-Known Member

    Welcome to the forum. I agree that a jackshaft kit that allows you to shift gears is needed for fun trail riding unless you live in a very flat area.
  4. KCvale

    KCvale Motorized Bicycle Vendor

    80cc MB motors aren't 80, they are 66cc, and have about all the power your typical bicycle can take.
    The Grubee Skyhawk 66c is a good choice.
    The 48cc has the same top end, the 66 just has much more torque.

    Riding it on the roadway depends on your state laws.
    For example in Arizona it has to be a 48cc or smaller motor to be classified as still just a bicycle. Anything larger makes it a motorized vehicle subject to having a drivers license, tags, emissions, all the safety equipment a motorcycle has, and insurance.

    My next MB build about to start will be based on a MX bike and use a Jackshaft kit.

    I won't go into how it works in this post, but yes, that is what you need.
    Just do a forum search on Jackshaft or visit their web site, Sick Bike Parts, they have ad links right here on the site.

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