ok long post. get ready.
So we built a motorized bike today. The motor was a 50cc solution from Handheld Items. It was a good deal but there were some issues with delivery. They requested a signature and I had it sent to the house rather than the office. err..
A new chain ring is placed on the right side of the rear wheel so the original chain ring is left intact. The attachment is interesting in that two rings of rubber sheeting are bolted to the wheel.
The engine bolts onto the frame easily if you have an older frame. A newer ovoid style frame would make it significantly more difficult. We fortunately had a older Murray (I think a Santa Cruz)and it bolted up quickly. The coil and controls are fitted up after the engine is mounted.
Once the engine was bolted up, we were able to work on the chain. This was the most difficult part of the entire build. I have a chain breaker for bicycles but 1)I could not find it and 2) had it been found I'm almost positive it wouldn't have fit the large chain of the kit. To install the chain the motor must be turned over by hand. I dropped a little oil in the spark plug hole just to make sure the engine was lubricated while I was doing this. We used a pair of pliers to grab the teeth and give a little more leverage as we fed the chain through.
To start the engine, you pull in the clutch and pedal away. The engine engages when you let go of the clutch and it starts almost silently. It helps if you continue pedaling for a moment to help the engine. Before long it takes over and you are clipping right along. I haven't opened it up entirely because without proper suspension I'm a little hesitant.
Verdict: Totally fun.