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CRF250 FC Revalve stack

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I tore down my 05 CRF250 forks and just wanted to post the stacks that were done by Factory Connection. This is for the Fork Cap Assembly (Base Valve)

Not quite sure how to list this stuff but here goes- I'll just go from the top down:

All 6mm Inner Diameter

5x 16mm

15

14

13

12

11

16

2mmspacer (whats' this?)

5x 30

purple spacer(what's this?)

19

20

21

22

23

24

25

26

27

28

29

11x30

It was valved for rough sand and hack like Southwick or Glen Hellen type stuff. I am putting .46 springs in and am trying to keep it plush but more progressive.

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Maybe a picture of the parts would be useful?

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basically it looks like they removed about 4 low speed shims.

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What about the mid?

Also if you can describe the "Whats this?" parts a little better.

I would assume that all the shims are .1mm thick?

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I'm sorry, but I'm having trouble visualizing that shim configuration. Would it be too much trouble to enter the information in a format such as this?

16-30.1

28.1

29.1

28.1

27.1

26.1

25.1

24.1

23.1

22.1

21.1

20.1

19.1

18.1

30x2.00 base plate

16.2

11.2

12.1

13.1

14.1

15.1

9-16.1

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I'm sorry, but I'm having trouble visualizing that shim configuration. Would it be too much trouble to enter the information in a format such as this?

16-30.1

28.1

29.1

28.1

27.1

26.1

25.1

24.1

23.1

22.1

21.1

20.1

19.1

18.1

30x2.00 base plate

16.2

11.2

12.1

13.1

14.1

15.1

9-16.1

That looks better. So it's a base plate. I know I am playing with the big boys now...Thank You:ride:

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Now you know another reason for aftermarket valves , so it won`t do any good for someone to post stacks for everyone to copy.

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Now you know another reason for aftermarket valves , so it won`t do any good for someone to post stacks for everyone to copy.

I posted this to see if someone will help me learn what was done and what was changed. I am new to this and am trying to learn that's all Hellboy:ride:

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It just looks at the moment like they removed a bit of ls damping, but they may have stiffened the mid(and or closed up the float) so its not the whole story unless we can see the mid setup(shims and float)

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Ok lets straighten things out...this is what the last '05 CRF250 that was stock had it it when I cracked it open.

OEM BaseValve

16-30.1

1-29.1

1-28.1

1-27.1

1-26.1

1-25.1

1-24.1

1-23.1

1-22.1

1-21.1

1-20.1

1-19.1

1-18.1

Base

10-16.1

1-15.1

1-14.1

1-13.1

1-12.1

1-11.2

1-16.2

Looks like they added a 28x.1 and removed 1-16x.1 from the bleed. The '06 stack if I remember correctly has either a 25 or 26 added before the 29 and has only 1-16x.1 on the bleed..w/.25 on the MV float..:applause:

Would be interested to see the MV and the changes if any that were done there. The OEM MV is 6-20.1 and 4-17.1 with a .1mm of float

FC BaseValve

16-30.1

1-28.1

1-29.1

1-28.1

1-27.1

1-26.1

1-25.1

1-24.1

1-23.1

1-22.1

1-21.1

1-20.1

1-19.1

1-18.1

Base

9-16.1

1-15.1

1-14.1

1-13.1

1-12.1

1-11.2

1-16.2

Post the mid-valve....

How does the fork perform for you? What works and what doesn't?

theDogger

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The gemtleman on the first page listed them like this because I guess mine was incorrect. Perhaps you can decipher my original post. I know I have 11-30s instead of 16. I closed it up today. I should have got the mids but I am going in baby steps. I will get the mid in a couple months. I'm lame but Trying to learn at least what the changes mean in the base valving.

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I tore down my 05 CRF250 forks and just wanted to post the stacks that were done by Factory Connection. This is for the Fork Cap Assembly (Base Valve)

Not quite sure how to list this stuff but here goes- I'll just go from the top down:

All 6mm Inner Diameter

5x 16mm

15

14

13

12

11

16

2mmspacer (whats' this?)

5x 30

purple spacer(what's this?)

19

20

21

22

23

24

25

26

27

28

29

11x30

It was valved for rough sand and hack like Southwick or Glen Hellen type stuff. I am putting .46 springs in and am trying to keep it plush but more progressive.

This is what I have in there but listed backwards. More of a change over stock.

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Do you remember the size & thickness of the purple spacer you listed?

Not sure. Close to 11mm X .1mm -6mm ID Thought it was a small spacer between the two different sizes- there was a good jump in diameter after the spacer.

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If that "spacer" is around 11mm & placed at the bottom of the stack (under the 19) it will soften the stack. And it's not a spacer, it's the clamping shim. The smallest shim on the bottom of the stack is called a clamping shim or pivot shim & sets the force for the whole stack. The smaller the clamping shim, the softer the stack becomes.

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The gemtleman on the first page listed them like this because I guess mine was incorrect. Perhaps you can decipher my original post. I know I have 11-30s instead of 16. I closed it up today. I should have got the mids but I am going in baby steps. I will get the mid in a couple months. I'm lame but Trying to learn at least what the changes mean in the base valving.

Hey, you did good! I get the jest of what that valve-stack was supposed to be about.

We've discussed very, very similar valve-stacks recently in fact. It's a single stage stack that's been lightened up a bit by removing five 30mm shims from a stock sixteen 30mm shims. This is very common. Then they set the five removed 30mm shims on top of the base-plate in order to maintain the same distance from the base-plate to the piston. This is so everything bolts up nicely as it would stock.

They replaced the last 18mm clamp shim with something smaller, which is your purple shim ( heat-treated ) - it's actually blue :applause: Don't worry, many people have trouble with certain blues and purples. My Dad still believes he drives a purple truck. It's blue as hell...

It was probably an even number shim, 12mm or 14mm, I bet.

The rest are the compression valving shims that you can screw around with all you want and it never seems to add up to squat.

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OK. Thanks!:applause:

Basically it was switched to soften the damping? So to stiffen can you go 4 &12 or 3 &13.

The small blue shim (clamp shim) Replaced the 18 to soften it more? Wonder if I should throw the 18 back in.

I just put in one unit stiffer main springs and Mobil ATF (Both Chambers!!) 380cc outter.

I have lighter IC springs and I am trying to find a middle ground with the ATF rather than going to a heavier IC spring.

This is my attempt to keep it soft on top but then get much more progressive.

FC Revalved this a while ago when I was much slower and I now blow through a bit.

I did the forks yesterday with those new FC updated seals (springs on both side- a bit tighter) and even comparing thm off the bench feels better than they did.....and I can't beleive the brown sludge that I took out. Hopefully this ATF will look better.:applause:

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