What's the RC51 set-up with... or is it ALL OEM? Forks have or have not been rework?
IF Everything is OEM 100% stock.. Your forks,.. You can screw the preload down all the way right now because the OEM spring is not Strong enough for your weight... I mean it will work but it is NOT Oppimunm <sp>
Bucking you out of the bike is tell me, Your compression IS too slow and your Rebound is too Fast! One or the other but sounds like it could be both..
Your Shock... First thing.. set preload... and then, I would start both compression fast and rebound in the mid. of the range and adj. from there to suite your riding..?
Same with the forks too by the way.. Going for quick reacting legs to smooth out your ride... Also. take\make notes of adjustments and where they're set.