Thanks you guys,
I used a Micargi Stealth cruiser which you can get at a bike shop (not walmart) and a raw 80cc engine.
I suggest shaving off one side of the chains bumps so it can have better clearance from the back tire. Also you will have to take the sprocket to a machine shop so they can increase the size of the diameter. This will allow clearance from the coaster brake arm. (let the machine show measure the diameter of the coaster brake. Use black zip ties to keep the black theme going on. The only thing to worry about when using a Micargi cruiser is to be careful with potholes. It doesn't have suspension like a mountain bike so don't plan to take it on the dirt or you'll damage the frame. I suggest to drill into the frame rather than having the u clamp, my preference. You'll make it more secure. (I haven't tried a u clamp so don't think I did try one before) Thanks guys!