rebuilding raptor 660 motor


I have the motor apart on my bench, have the head and camshaft off. Looking at the piston and it seems like there is a large gap between the piston and the cylinder, I can stick my fingernail in between the two, when the other side of the piston is flush with the cylinder wall, is that normal? I will be measuring it later.

I bought a new piston and rings for it since it was burning oil, but the valves have also not been touched for a year, if the valves were off could it burn oil? About half a quart a week, as well as smoking on startup.

Should there be oil around the valves and camshaft? Or are my seals out? This is my first time taking apart this motor.

you probably have too much of a gap between your sleeve and piston

Yes, there should be oil around the cam and valves. The valve guides need to be replaced that is why it smokes on start up.

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