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New to valving, need help to understand effect of certain changes

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1) is a stock BV shim stack for a 06 yz125

2) is the BV shim stack as I got the bike with a revalve **changes are in bold

1)

32-0.11 (15)

30.0.11

28-0.11

26-0.11

24-0.11

22-0.11

20-0.11

18-0.11

16-0.11

14-0.25 (2)

plate

11-0.25 (4)

14-0.11

16-0.11

18-0.11

20-0.11

22-0.11 (2)

2)

32-0.11 (16)

30.0.11

26-0.1

28-0.11

26-0.11

24-0.11

22-0.11

20-0.11

18-0.11

16-0.11

16-0.11

14-0.25 (2)

2-plate

11-0.25 (4) All shims below the plate have been removed

14-0.11

16-0.11

18-0.11

20-0.11

22-0.11 (2)

So if I understand correctly the addition of the face shim (32.11) would stiffen the LS comp. The pivot below the face shims would soften HS comp and the addition of the 16.11 before the plate would stiffen both HS & LS.

(Please correct me if I am wrong as I am trying to learn)

What effect does removing all of the shims below the plate have?

Thanks

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the extra face shim will offset a little the loss of low speed due to the cross over.The 16.11 in the high speed will not have much effect as shims that low dont, it will mostly affect the high speed side as thats where it sits.

The 2nd stack is interesting, they have taken the clamp shim out(11,25) and are using the 14 as the new clamp, this will stiffen that whole stack considerably.

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Marcus, I think that they have removed the bleed stack completely. I wonder if the rider feeling differs from stock at all. Very small changes, if they have not touched the MV or rebound. 14mm was stock clamp in this bike 06.

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Jarkko sorry you are right, all the bleed shims removed.

Yes by adding a cross over, then adding a face shim and a shim in the hs stack, you end up with a 2 stage stack that will mimac a single stage std stack, well spotted.

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If the crossover would be smaller, like 20-22 it would feel slightly plusher than stock in small hack.

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i wonder if the mid is a 2 stage or maybe softer than std? more float?

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Every 11-0.25 shims below alu plates are removed.:lol: There isn't free bleed at all. There need to be at least one 11-0.25 or equal. I wonder how that com adjuster will bahave with that setting.:ride:

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Every 11-0.25 shims below alu plates are removed.:bonk: There isn't free bleed at all. There need to be at least one 11-0.25 or equal. I wonder how that com adjuster will bahave with that setting.:lol:

Nice catch! I missed that. If the plate seals the end of the tap the clicker would be locked out...

:ride:

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Thanks for your replies.

In looking at the bv again today I missed a 11.25 under the second plate.

The MV has not been taken apart.

So what is the effect of having the free bleed(?) removed.

I do not know the guy that originally had this done; I purchased the bike on consignment from a delear.

I am 160# 5'10", fast, fairly aggressive vet B rider and find the forks slightly harsh on the small stuff and too soft overall- bottom out.

Currently running C-7, R-11, 340cc of oil and .42 springs.

any suggestions

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Go back to stock as a base line...they work pretty good stock. What area of ontario are you from?

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Use stock shimstack -4 face shims and reverse the bleedstack or at least leave the 4x11,25 under the plate.

I have tried a couple of times with a crossover using stock mv and i don`t like the feeling.

What do you mean with the second plate? I have only seen one in them.

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If you don't have any free bleed and by pass holes are very restricted (or closed), your fork feel very harsh in small pumbs. There need to be higher pressure in the cartridge to get the shim stack open (faster piston rod movements make this happen). Com adjuster controls oil by passing through the bv body, it is like a low speed circuit. Some fork uses low speed stacks to get fork rides higher.

In your case those by pass holes are closed with that alu base plate. When com clicker is turned in, result will be *no free bleed at all*. Also might cause some free piston problems I think.

Hope this help:thumbsup:

Jussi

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What do you mean with the second plate? I have only seen one in them.

KYB uses two alu base plates when there aren't used the low speed stacks. This is to get the total height of the stack adjusted correct.

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Go back to stock as a base line...they work pretty good stock. What area of ontario are you from?

Hamilton

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Use stock shimstack -4 face shims and reverse the bleedstack or at least leave the 4x11,25 under the plate.

I have tried a couple of times with a crossover using stock mv and i don`t like the feeling.

What do you mean with the second plate? I have only seen one in them.

I was thinking of returning to stock. If I return to stock less 4 face shims will that not make my bottoming problem worse?

Or could the bottoming then be controlled with the clicker adjustment?

"reverse the bleedstack or at least leave the 4x11,25 under the plate" I'm not sure what you mean by this

What I'm looking for is is the forks to have less hs and more ls.

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For those of you with shim stack experience, what kind of set up do my forks currently have?

and thanks again for your help.

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as we said your setup is close to std, but done using a 2 stage stack instead of a single stage, you should try std shim stack -4 face shims , that should work better as its a single stage.Single stages tend to be more predicatable with no damping gaps or spikes.

If you want more low speed less high, use the std stack, but remove every other of the hs shims, eg use 30, remove 28, use 26, remove 24 etc.

Or you could try std shim stack with softer ics springs, that maybe a better setup.

Its hard to say which way is best, there is more than one way to do it.

Dont worry about the bleed stack, by the sounds of it yours is sorted via a 2nd plate.

you could also put your spare shims you remove under the plate to space out the bleed stack to keep overall height the same.

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I was thinking of returning to stock. If I return to stock less 4 face shims will that not make my bottoming problem worse?

Or could the bottoming then be controlled with the clicker adjustment?

"reverse the bleedstack or at least leave the 4x11,25 under the plate" I'm not sure what you mean by this

What I'm looking for is is the forks to have less hs and more ls.

Why 4 x 11 shims under the plate: You need to have some space between the back plate shim and piston stem. Otherwise your clicker circuit is blocked, which is very hard to believe. Anyway that is what you have explained so far. How anyone would do such a change? Do you feel any kind of difference when altering comp clicker to either direction?

Try it completely stock first. Just replicate the complete stock stack and start from there. It will be stiffer for bottoming and at the same time activating the clicker circuit again allows some free bleed and it will work better in small hack.

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I was thinking of returning to stock. If I return to stock less 4 face shims will that not make my bottoming problem worse?

Or could the bottoming then be controlled with the clicker adjustment?

"reverse the bleedstack or at least leave the 4x11,25 under the plate" I'm not sure what you mean by this

What I'm looking for is is the forks to have less hs and more ls.

O i was under the impression that you did HS and enduro stuff..

Higher oillevel is some cure for bottoming.

32-0.11 (15)

30.0.11

28-0.11

26-0.11

24-0.11

22-0.11

20-0.11

18-0.11

16-0.11

14-0.25 (2)

plate

this is the reversed stack.

22-0.11 (2)

20-0.11

18-0.11

16-0.11

14-0.11

11-0.25 (4)

I use a -08 yz250f with -4 faceshims 0,45kg spring no bleedstack and can`t remember when im last bottoming it , but then im not so aggressive when im doing mx but weigh almost 220 lbs full dressed.

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