Be careful what you ask! Now the long winded answer with two stroke theory. 2 stroke engines work much differently than their 4 stroke counterparts. They actually have more in common with a rotary engine and NOTHING in common with a Harley. They have no crankcase oil, meaning they rely on a fuel/oil mix for lubrication. They also require a well sealed crankcase to provide primary compression. this is because they rely on pressure to draw the fuel into the case and push it up through the transfer ports to the combustion chamber where it is fired and held in place by the reversion force created by the funny looking expansion chamber/exhaust pipe. This is a piston port/ reed valve engine. Boyesen makes good affordable performance fiberglass reed valves for these. Just follow the simple instructions. The stock reeds are durable stainless and carbon fiber (expensive and chip easy-not my choice) reeds are available. Ski-Doo snowmobiles have available different thickness base gaskets. Not only does thinning the base gaskets increase compression it changes port "timing". By installing a thinner gasket you effectively cam up your engine. When I had my RD 350 I used only silicone sealer with NO gasket and frequently replaced it. Went like crazy. For a good chunk of change I could head shave, port and blueprint it and scare the crap out of you!! Good score! My advise would be to spray paint the gaskets with whatever is around your shop and install while still tacky. Inspect the reeds to make sure they are sealing properly and enjoy. If you have more questions feel free to call me, Wayne at 596-5414. On second thought, what a piece of crap-tell you what I'll take it off your hands as a favor....Luck and CHEERS.
