Hi! I have Kawasaki KDX 125 enduro bike and i have bolted to it 1991 125 kx cylinder,piston,pro circuit exhaust,36mm keihin and new boysen rad valve the engine has just been rebuilt and there are no leaks. The problem is that the engine has no power even it takes rpms well and runs relatively good. Could the problem be in the piston and the cylinder head because i have apparently 1991 125kx cylinder head which has the pin.
So do i have the wrong head or piston in my engine because i have the flat piston and the head witch has the pin. Eric Gorr tells in his book that you are not alloud to mix 1990 and 1991 cylinders. Which has thinner 0.26 head gasket 90 or 91? the exploded wiew offers the same to both 90 and 91...
Bottom-end is in good condition, jetting is OK, no leaks etc...no too much oil...no bad gas...
Or could spark timing difference between KDX and KX do THAT big difference in power, without other running problems..
btw im from EU
Thanks,
Wille