I have an 88 honda 300 fourtrax 4X4 and when i am in 5th gear and at high rpm's i am losing power and only getting maybe 25-30 mph out of it, i am also losing oil out of the top end gasket, it also begins to shift poorly and just does not run right at all. Would replacing the cylinder, rings, gaskets, valves, and clutch plates possibly solve the problem ????

 

even Hondas will wear out after 22 years...sounds like it's time for a rebuild

 

Is there lots of exhaust pressure getting out the back ..