Friction Drive Motorized Bicycle W/ GX25




All you need for this project is...

-Bike $50

-Engine $25

-Throttle lever $5

-Angle iron $5

-Flat stock $7

-Turnbuckle $7

-3rd bearing peg support $3

-5/16in 4in long bolt w/ nut and spacers $5

- BMX drive peg $3 for 2 pegs

All the tools you need...

-Drill with 1/4in and 3/16in bits

-Cut off wheel / Die grinder / Dremel


Total price for everything was $110ish which includes the bike itself.

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Step 1: Getting an Engine

Get an engine that is 50cc or lower. You can go to craigslist and search for weed wacker engine or if you already have an engine laying around then your set. My engine is a Honda GX25, I chose this because its quiet and reliable.

Step 2: Picking a Peg

Remember that the bigger the peg you have it will give you a high top speed but a horrible acceleration.The smaller the peg the more low-end torque you will have, but low top speed. You can get the peg I got on eBay for $3 from China.

Step 3: Peg Mount

I used a clutch drum from a weedeater and cut it up to mount on to the back of the flywheel so I could mount the peg.

Step 4: Mounts for the Bike

I got a 5/8 5in long bolt with some 1 1/2 coupler nuts with two 1/2in U-bolts. together it looks like that. but later used the bike rack mounts on my frame. Also used a turnbuckle to raise and lower the engine off the wheel.

Step 5: Then Your DONE

Start it up and ride it

(Currently not finished that's why there's no picture, I'll post picture and video when complete)

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    3 Discussions


    1 year ago

    k9troeppl did you get this working? any issues? was the flywheel strong enough to withstand forces from your bike wheel? thanks


    1 year ago

    That's why I making one


    1 year ago

    It would be really fun to have one of these :)