I just rode my new '07 YZ450F this past weekend. I had a WR250F before and liked the 13/53 gearing it came with for trail riding like I do. I am needing to change the rear 49 that this bike came with( never got out of 3rd gear), but I am not sure the tooth count to use. The parts guy at the dealer said he uses a 50T on his bike. My question is will this be enough to trail ride or should I go to a higher tooth count, because of the different tranny gearing between the WR and the YZ?