Hi. I couldn't find a thread on this, so I'm starting one of my own. I bought parts to build an engine from gasbike.net. I bought a crankcase with a centrifugal clutch and a top-end rebuild kit. I assembled the engine while a more knowledgeable buddy supervised. the engine does not have a necessity for a manual clutch as far as I can tell. In fact, there are screws where certain parts for the manual clutch would normally go. The problem is this. The cent clutch is always trying to grab and making a lot of noise. It not only makes a noise that concerns me when the engine is off, it makes it difficult to start as well. From what I understand, it requires some sort of maintenance or adjustment. I found instructions on a website called eHow explaining how to adjust it, but they didnt help. the instructions said to loosen the large nut holding the clutch on and move the adjuster screw that is behind the large nut. on my clutch, there is no adjuster screw, only a large nut. If anyone can give me accurate advice, i would appreciate it.