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Shim Stack Questions

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I got my Shock Shim Stack measured tonight. I am trying to decipher where the clamping shim is on compression and where the transition from HS to LS would be. I think some of the shims on the bottom may just be for spacing? I am 6'3 240 lb MX C rider and would like to stiffen the HS but keep the low speed from having me feel every bump. The reason I want to stiffen the compression is that it was bottoming a little too much.  The numbers are what I measured with caliper so please point if they are not standard shim thicknesses. 2011 yz450 Spring 0.53 Fork 6.3 Shock

Shim Stack COMPRESSION STACK

OD  ID  THK.

PISTON

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

38 12 0.11

44 12 0.16

42 12 0.17

40 12 0.17

38 12 0.17

36 12 0.17

34 12 0.17

32 12 0.17

30 12 0.17

28 12 0.16

26 12 0.16

24 12 0.16

22 12 0.23

21 12 0.21

44 12 0.17

44 12 0.17

44 12 0.17

44 12 0.17

SPACER AT BOTTOM

Edited by JLB943

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...

REBOUND STACK

OD  ID  THK.

SPACER 26 x12 X3

 

25 12 0.3

28 12 0.3

30 12 0.3

32 12 0.3

34 12 0.3

36 12 0.3

38 12 0.32

40 12 0.32

29 12 0.11

40 12 0.2

40 12 0.2

40 12 0.2

PISTON

.Any help or input would really be appreciated.

Edited by JLB943

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The first seven (7) 44 x 12 x .2 are the low speed, the 38 x 12 x .1 is the cross over.

Under the crossover is the high speed stack until the 21 clamp shim.  Yes the 44's under this are for spacing or backers.  You could put some of these just under the cross over if that is what you're after.  You could also remove the 21 clamp and make the 22 the clamp which would make the entire stack stiffer.

 

I'm sure more knowledgeable guys will chime in shortly with more educated suggestions than mine.

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Usually shim thicknesses are .1, .15, .2 and .25 but probably just slight error in calipers.

Do you have spare shims? you could replace some thin shims with thicker ones lower in the stack to firm it up a bit also.

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The rebound looks too light and the compression does in the hs

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I ended up doing a sketch for this so I could visualize it.

For the compression, I am thinking of removing 2 the spacers from the bottom and adding 2X 40 X .20 one down from the crossover. The removing the smaller clamp shim and using the one above as the clamp.

 

How do you think these changes will effect the HS? Will it beome too stiff?

 

I have to look at the rebound and maybe sketch this. I need to see visual representation.

Single Side of Compression Stack.jpg

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COMPRESSION STACK

OD  ID  THK.

PISTON

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

44 12 0.2

38 12 0.2

44 12 0.16

42 12 0.17

40 12 0.20

40 12 0.20

40 12 0.17

38 12 0.17

36 12 0.17

34 12 0.17

32 12 0.17

30 12 0.17

28 12 0.16

26 12 0.16

24 12 0.16

22 12 0.23

44 12 0.17

44 12 0.17

SPACER AT BOTTOM

 

Rebound

 

SPACER 26 x12 X3

 

25 12 0.3

28 12 0.3

30 12 0.3

32 12 0.3

34 12 0.3

36 12 0.3

38 12 0.32

40 12 0.32

29 12 0.11

40 12 0.2

40 12 0.2

40 12 0.2

40 12 0.3

40 12 0.3

40 12 0.3

PISTON

 

These are changes, I am going with. Hoping this doesn't end up making things worse.

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