I have wanted to do this to a bike ever since I was a young boy, and now as an adult I am looking to create my own DIY motor bike, not only for me but me and my neighbor are going to build a second one after this one so we can race around our block. Then the kids can enjoy it. My donor bike is a Schwinn boy's Falcon BMX bike 20" The donor motor is a Mcculough EZ-Start 31cc I have been doing a ton of research and I am not keen to idea of a direct drive method, but I am willing to have a go at a gear method. My only issue is how to mount the drive gear to the clutch bell. I do have a MIG Welder so welding something is not an issue for me. If anyone has any photos of what they have done like this I would really like to see how it was done if not I am sure I will figure out a way to attach a gear to the clutch with a support bearing so it has maximum support & strength.