Test #1
Used oil 7.5 with stock springs--Compresion slight change, rebound neaded adjustment to faster in order to soak up bumbs.
Test #2
Used oil w10 with stock springs--Compresion fair change, rebound adjustment even faster in order to soak up bumps, did not like the rebound as much as compresion, when fast enough for bumps was too fast for jumps.
Test #3
Used oil w10 with Heavier springs--Compresion nice feeling when landing from jumps fair enough in bumps and turns, rebound worked well in jumps and bumps
Bike used
yz450f 2004
Heavier springs- 0.48