Identifying Shim Stack 2007 CRF250R Shock

[tylerbernauer]

Hello,

Im pretty new to the whole suspension thing so I'm wondering if someone could help me out. I have a 2007 CRF250R shock that I decided to rebuild as practice. I pulled it apart and noticed the peening was already filed off so I checked the shim stack to see what changes have been made. Would anyone be able to point out what these changes would of accomplished. I'll post the stack I found and the stack I believe to be stock. Thanks in advance.

STOCK                          STACK THAT I HAVE

Compression                COMPRESSION

44.2x7                          44.2x7

44.15x6                        44.15x4

37.15                           34.10

30.15                           28.10

42.2x2                         44.25x2

40.25                           40.25

38.25                           38.25

36.25                          36.25

34.25                          34.25

32.25                          32.25

31.25                          30.25

30.25                          28.3

29.3                            26.3

28.3                           24.3

27.3                           22.3

26.3                           PLATE 44.5mm X 5mm

25.3                           44.3

24.3

23.3

22.3

25.6x3

Rebound                  REBOUND               

40.2x2                      40.2x6

25.1                          28.2

40.3                          40.3

38.3                          38.3

36.3                          36.3

34.3                          34.3

32.3                         32.3

31.3                         30.3

30.3                         28.3

29.3                         26.3

28.3                         24.3

27.3                         29.3x6

26.3

 

 

 

[chelder]

Interesting stack, for sure the compression is really soft and a lot of low speed rebound and a faster high speed rebound, Would need to put in into restackor, one of the pros will be along soon....

[mog]

The thing is the 0.1mm cross over shims allow the high speed stack to support the low speed stack more ,and the 44.25 in the high speed mean it's much former there than STD ,like much much firmer ,the clamp us much smaller

That mid part if the stack confuses things ,I think the softer clamp makes it softer overall

The rebound is what most people use to get some control of low speed rebound

[chelder]

Ah yes I missed the .25's 

[tylerbernauer]

Thanks for the responses guys. A little over my head but i'm learning. Once i get the tools ill pull the forks apart, im assuming they will be valved as well.

I have the shock back together and it rebounded good, although it is pretty hard to push down. There is also a small amount of noise during the last 1/4" of rebound or so. Could this be the top out spring or do you think I have some air left in there?

[mog]

Air imo

[chelder]

Air

[MX Tuner]

Mog, you're still a moron.

The stack you list is very similar to what I'd do. I wouldn't quite do it the same way but the end result would be close to what I'd do. Its taken me almost 25 years of doing suspension to know what shims really do what in respect to the changes. If it works, I wouldn't mess with it. As long as you have some clicker adjustments available, you should be in good shape. I've seen some really f*cked up shim stacks- I just shake my head and put a good stack in it. The stack you show looks very reasonable and should work well.

[mog]

I guess that was a joke and I missed it ?

[MX Tuner]

Nope, no joke.

[chelder]

5 hours ago, MX Tuner said:

Nope, no joke.

I have no idea what's going on here but seems a bit harsh Mog is always coming in here helping people out and is a valuable contributor from everything I have seen.

Anyway thanks Mog

[tylerbernauer]

Hey mog,

i've done some researching on here and saw you suggested 14mm dia Standard HSS Annular Hole Cutter c/w Arbor for doing Showa shocks, which i believe is a 10.5mm ID if i remember correctly from your thread. Do you still use this or have you found a better way? If you do still use it do you know what size you use for KYB shocks. I don't have one to currently check with.

I'm currently trying to get a little collection of suspension related tools. I ordered a few Factory Wrench Tools for KYB SSS and Showa Twin Chamber forks. https://factorywrenchtools.com/. Ive also ordered a few of those race tech compression adjuster sockets.

 

Thanks

[mog]

Yes still use it , not sure on the kyb however