05 motor work

[BlackTrx440ex]

i want to put a sparks piston 13;5;1 and a hottcam stage2 will it make a big differance?

I would say yes.

I just put in a CP 12:1 piston and a 02 CRF cam when I installed the updated crank. The power difference is definitely noticeable. You might want to get a lower compression piston so you can run pump gas. I'm happy with mine.