Trying to tame my 03 YZ450F for the woods. reinstalled the stock exhaust (had Pro Circuit Ti race system) and now I'm going to install a Rekluse clutch. how much extra weight does the rekluse add to the flywheel, 3oz? Also how much heavier is the 05 YZ450F vs the 03 YZ450F? Considering that option if the rekluse doesn't do it. thanks.