Bike size

[Nathan]

Want to put motor on my boys 20" mountain bike. No worries on safety he is amazing on anything with wheels or a motor and can handle speed. Want to know cheapest way to do it and what model motor kit I should use...

 

[crassius]

I'd guess that a friction drive would be all the would fit easily.

 

[butre]

you will probably have to go rack mount. what are the dimensions of the triangle in the frame?

 

[Deleted member 12676]

cut the top frame tube so the cylinder head has space.
Then weld up a curved tube to reconnect the frame together.