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Shim stack experimentation (CRF450X) - request guru opinions

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Question for those in the know here.  I am helping a buddy with his stock 2007 CRF450X suspension that I am certain has never been opened up before - not a single mark on the fork caps, and the oil that came out of there looked like maple syrup.  The shock oil was just really, really dirty.  So I did fork bushings and seals for him and put 350cc in each outer (no manual...just best guess based on the manual amount of 330-ish and others' online setups with around 380...may need to add some).  Stock springs for now, front and rear.  We'll see where his sag ends up, but I think he may need to go up a rate or two in the rear (stock is 5.5).

So in the mean time, I've had his shock at my house and I've got it back together with new rebuild parts and told him maybe I'd try a little home revalve and if it's terrible, I'll just put it back to stock.  He's around 195 with gear, novice level off road rider, and we're on mostly flat/fast sandy single and two track, with some deep sand, no rocks, few jumps, and some logs here and there.  I didn't touch the valving in the forks, but here is the stock shock shim stacks (say that 10x fast), with side notes of what I did.  Looking for opinions on what, if any difference this will make, anticipating that he'll stiffen up the rear spring a bit.

  • (REBOUND)
  • Nut
  • Heavy washer
  • 28  .30
  • 29  .30
  • 30  .30 
  • 32  .30  (I added an additional 32 .30, so 2x 32 .30 now)
  • 34  .30
  • 36  .30
  • 38  .25
  • 40  .25
  • 24  .10
  • 40  .20 (3)  (I changed out the lowest face shim for a 40 .25, so it's a 40 .25 and 2x 40 .20s)
  • VALVE
  • (COMPRESSION)
  • 44  .20 (15) (I removed one, so 14x 44 .20s now)
  • 44  .15 (6)
  • 38  .15
  • 30  .15
  • 44  .25  (I removed this shim and did not replace it)
  • 42  .25
  • 40  .25
  • 38  .30
  • 36  .30
  • 34  .30
  • 32  .30
  • 30  .30
  • 28  .30
  • 27  .30
  • 26  .30
  • 25  .30
  • 24  .30
  • 23  .30
  • 22  .30
  • 30  .30 (3)
  • Heavy Washer

My thought process was to tighten up the low and mid speed rebound slightly in anticipation of the increased spring rate (and deal with it with clickers in the mean time if necessary), and then on compression, I figured since it's mostly flat here and with a stiffer spring helping to resist movement, slightly increasing flow might help with the smaller trail chop and short/fast piston movements.

I've worked on my KYB shock and SSS forks numerous times and have only fooled around with Race Tech's gold valves a couple of times, simply following their charts.  Never done guesswork like this and figured I'd see what you guys think before I put this thing back together.  I did read through some theory on Shim Restackor's website and a few other places, but don't have any practical revalve experience aside from RT kits.  Do you think these changes will make much of a difference?  

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How many rebound face shims were std ? 3 , if so you have made a small change, you can go to 6 face shims

On comp the changes will be small

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How many rebound face shims were std ? 3 , if so you have made a small change, you can go to 6 face shims

On comp the changes will be small

Yes, it was three rebound face shims, all I did was increase thickness of the bottom one. I'll as add a few more. My problem with the compression stack is I didn't want to change too much without really understanding what I'm doing. I figured one less face shim and one less mid-speed shim was "safe" especially for a novice rider on fairly smooth terrain.
thanks for looking at it, mog.
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So I ended up adding back in the rebound face shim I had replaced (40 .20) and added a 38 .20 just prior to the crossover, so now low speed rebound stack is:
24 .10 x-over
38 .20
(3) 40 .20
40 .25
VALVE

Stock was just the 3 40 .20s, so we'll see how this works.

I also removed another couple of compression face shims 15x 44 .20 stock down to 12 now and increased the thickness of the compression crossover from .15 to .20 in an effort to make the compression valving more progressive. Who knows, I'm shooting from the hip a little... It's all back together now, so we'll see how this works out!

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