making a electric bike.

has anyone ever tried turning a standard push bike into a electric one. ive been trying all day, using one of the spare 24v motors from a scooter, which im using as my robot axe drive. the problem i have come across is getting the chain to avoid the frame of the bike. spent all day fixing the motor, but i forgot that i was working with the bike upside-down, so when it was the right way the chain just hit the frame which stoped it from spinning.

just wanted to know if anyone has done this before, so that i can see how to get around my problem.

will post pics tommorow.