can anybody teach me how to convert grass cutter engine into bicyle motor?

Answer 1

I am sure this can be done. The problem you would have is that most lawnmower engines the drive shaft comes out the bottom (verticle) You would have to build a platform then manufacture a transfer to change the horizontal motion (verticle output shaft) into a verticle motion (horizontal output shaft).

It would be easier to find an old moped and mount that to a bicycle frame. And easiest of all would be to find a motor made for bicycles and mount that.

http://www.kingsmotorbikes.com/Engine_Kit1.htm

http://www.natlbike.com/bicycleengine/

Answer 2

Remove the pedals and the crank from the bicycle and weld a mounting plate to the frame for the engine to sit on. Then attach speed activated clutch with a pulley to the output shaft of the engine and replace the rear sprocket with a pulley. Install a drive belt between the engine and back wheel, weld on a couple of safety plates to protect you from the heat of the engine and the drive belt and you are done!