I’m still fairly new to karting, and am learning a lot. I have two questions in regards to the Parilla Leopard engine. I have the Original Style ’07. My first question is in regards to the piston. When I go to do a top end rebuild, how do I know which piston to get? I notice there are several sizes and red or greed dot.
My second question is I notice there are both sprint and road race clutches, what is the difference between them?
The replacement Pistons come in increments of 0.02m/m. A 54.02 m/m green piston will fit a 54.02 cylinder bore. If your bore size is 54.03, you will need the 54.02 red dot etc. etc. The clutches I can’t help you with.
The piston sizes actually are the sizes for the cylinder bore itself–the tolerance is pre-built into the piston supplied. Thus, you machine the bore to, for example, 54.20 and order the piston that corresponds to that size. The piston will not actually be 54.20, but will be slightly smaller. The green piston would be for a bore of 54.20 while red is slightly oversized, bore = 54.201.
The clutch is good and yes I rebuilt the whole bottom end, seals and everything. Just didn’t put in new a piston or rings. So I’m thinking its low compression that’s not letting the gas pump up to the motor. And the carb is in good condition everything’s clean and working.
Clutches… Supposedly the Road Race Clutch is build for higher temps and longer engagements. However, I converted to one when I went road racing and burned it up in a day. Went back to using the “Sprint” Shoe and never had a problem. May have been a fluke, but I wasn’t going to keep throwing money at it to test. YMMV