the best way to learn is with a TRX .15 engine. they are extremely restrictive, and are kind of hard to hurt performance if you mess up. Heck, experiment with a worn out sleeve. Why pay someone to do the same damn thing when you can get more horsepower out of your mill ON YOUR OWN? Free is the way to be!

whatever you do, just dont polish any of the work you have done... thats just for looks and actually hurts performance.