Re: Motorized Bicycle Take a Tip...Leave a Tip
From my involvement in cheap motorcycle racing, the very first thing to be done is to rebuild the engine the way it was designed, not how the factory built it on a Friday afternoon.
The people here who know the engine will run you through the steps required, so you'll be in safe hands.
There's a job called blueprinting, which means that any unwanted steps or roughnesses in areas where gases flow through the engine are removed. The barrel sits on the crankcase, and there can be edges of the metal of either protruding into the transfer ports and slowing up gas flow. The same point applies to the carburettor and manifold. You will need guiding through those stages.
Then the reassembly of the engine. Bolts and studs need to be tightened to the appropriate degree and in the correct sequence to avoid leakages and distortions that can reduce the engine's efficiency.
My team won it's class last year on a "shouldn't have" bike, which had little money spent on fast parts, but hours and hours on fitting and assembly.