what next?

[300ex mxracer]

im gonna tear into the top-end this winter and wondering what i should get. i was thinking a 11.1 standard bore piston, sparks mx cam and what kind of oversized valves shoud i get?is this the way to go? i race mx most of the time with a little riding in the fields.mods in sig.

[JOEX]

I've heard the 300ex head is very restrictive so a port job may be a something to look into. I'd also take it apart and check the wear on the cylinder before ordering a std. bore piston just in case it needs to be bored.