if y bolt a 350x bore up to 396cc on my 300ex is my crank will resist?
and how hp gain will i get?
what change shoul i do to the rest of the quad whit all this new POWER!

 

I have a question. Why not just put an entire 350x motor in your ex? I have a 91 250x with a 350x motor and I love it. The conversion is really very simple. The hardest part being the exhaust in which I had one made, but a custom pipe would have to be made for your bike by putting just the top end on. You would gain an extra forward gear, but you would lose reverse. Losing reverse didn't really bother me much.

 

well i think i will just bore up my stock
to 333cc! whit a high compretion piston
so what should i change whit this new power?