My bro has an '05 450r and is dying to put on the HRC cam to go with the sweet Yoshi trs system. He was worried about the compression. I think in '06 they bumped up the compression and I know that a hotter cam needs a little more compression.

We were wondering if the HRC cam is a good match on the older 450r's with the lower compression or should he drop in a higher compression piston to compensate?