How To: Build a motorized bicycle

Bikes Fun & Games

Dave made this informative video on how to attach a “Weed Eater” [string trimmer] motor to a bicycle. Used bicycles and string trimmers are easy to find and very cheap to buy. You could make this project for less than $100, maybe even less than $50. The information on modifying the clutch could be very useful in making robots too!

How To: Build a Weed Eater motorized bicycle

8 thoughts on “How To: Build a motorized bicycle

  1. Anonymous says:

    Red Green lives!

    Is there nothing in Ontario without rust?

  2. justDIY says:

    @anonymous … aah, the rust belt – just like Michigan, we love our rust.

    what makes me laugh is the statement that “Every city has a bearing supply store”. I guess Canadians really like their bearings, there’s nothing like that around me for at least 200 miles.

  3. acidrain69 says:

    Very nice DIY. If you don’t have access to the tools to build this yourself, there are kits out there that mount on a bike. I have one of the Grubee kits mounts on a Trek Antelope 800. Works pretty good, and you just need a screwdriver and maybe a drill depending on your frame diameters. Clutch is manual, you just let out the clutch while riding and that starts the engine. They usually run about $250. Not as cool from the DIY perspective, but much easier. If you have the engine sitting around anyway, you could always build a DIY generator using a regulated car alternator.

  4. says:


    NO, there is NOTHING without rust.
    It’s like a disease, plaguing all steel and iron-based products. Anything that isn’t stored during the winter eventually gets infected.

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