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my engine is decrompressing while i am ridding, it idles ok, so i went to the garage to get a new compleate set of gaskets, i have decided to strip the engine down and clean everything

its a 2 stroke engine so do you think that it is decrompressing due to carbon build up? ill let you know l8ter on, well thats if the gaskets come 2day

also do them engine cleaners you mix in with your fuel work i was thinking about trying some

My experience with a 2 stroke has been that a loss of power is either a blown head gasket or bad piston rings. Neither is a big job on a 2 stroke, just be sure to clean the carbon deposits from the exhaust ports when you have the jug off. The Yamaha " Ring Free " is designed to clean fuel systems in both 2 and 4 stroke engines. It's a good product.

What do you mean by 'decompressing'?

If you lose compession on a running engine, generally it backfires a few times until it stops running, and this happens fast... as long as it takes for the motor to wind down and stop.

If you mean you lose power when the motor is hot..... it could be one of several things. Least likely of all are bad gaskets, IMO. Bad rings usually make for very hard starting and power loss at all temps and RPM. The same applies to bad reed valves. You should get compression readings from the engine when both cold and hot. If it reads low, rings or reeds could be the cause. And if you do have to remove the top-end to do the rings, you'll need those new gaskets anyway, so no loss there.

Maybe the piston is cracked and it only opens as it gets hot.... but probably not.

I see you find it important to keep the exact details of the bike a secrect...

Does the bike have a powervalve? The mechanism of such valves tend to build up carbon and gunk, and this can cause the valve to stick. And loss of high RPM power is a syptom of a sticky powervalve.