66/80cc Engine on Pitbike Frame

[Pacodestaco]

Thinking of getting my hands on a junk 70cc pitbike and throwing the 66cc bicycle engine into the frame. Considering a Honda crf70 is 130lbs completely build I couldn't imagine the frame being much heavier then a bicycle frame. And installing automatic transmission will assist with not having pedals. Has anyone attempted this before or have any suggestions on how I should approach this project?

 

[junglepig]

Thinking of getting my hands on a junk 70cc pitbike and throwing the 66cc bicycle engine into the frame. Considering a Honda crf70 is 130lbs completely build I couldn't imagine the frame being much heavier then a bicycle frame. And installing automatic transmission will assist with not having pedals. Has anyone attempted this before or have any suggestions on how I should approach this project?

Why would you opt for the bicycle engine?
Just to see if you can?

 

[Pacodestaco]

Why would you opt for the bicycle engine?
Just to see if you can?

Pretty much, not much loss of power from the 70cc 4 stroke other then having a shiftable transmission. I ride off highway and hardtails make it very uncomfortable. Just a fun project, of course looking into cr125 but way out of price range right now just want to play in the snow

 

[junglepig]

Sounds fun. I have no help or advice to offer you, except go for it if you find the right junk bike.
If possible, I think I'd try to repair the original engine though and have the advantage of the multiple gears.

Other, much more experienced folks here may have truly helpful advice...

 

[curtisfox]

winter project: https://motorbicycling.com/threads/motorized-kickslead.43361/#post-442366 ...........Curt