wp 48mm mid valve bleed

[prcucuma]

Did anybody try to put a smaller shim onto the piston for a certain amount of free bleed on a 48mm wp 2003 fork? Something like:

piston
20x0.1
24x0.1 (5x)
22x0.1 (2x)
20x0.1
spring

I am trying to make the forks response better on sharp edges. I made the clamping shim 0.5mm smaller and removed some low speed damping by removing one of the 24x0.1 on the base valve and opening the comp clicker, but it wasn't enough. So the next thing might be to work on the mid valve.
Any comment welcome!

 

[marcusgunby]

I rode a set of SXS forks with a similar setup to your suggestion-they were very nice-sadly i only know it had a bleed shim-not the actual stack.

 

this is for the base valve-not the mid which you are refering to-a bleed shim wont work there as it opens a good amount already ie plenty of free bleed.

 

[DEANSFASTWAY]

Prcuma youll want to be careful so as not to bypass the rebound circuit, It could affect that .

 

[prcucuma]

I was likely to try this setup on the mid valve, even despite the fact that there is quite some bleed...
If it would soften the rebound to much I might stiffen that shim stack.
The only problem is that I don't have enough time to try it th e next few weeks. But maybe I will try it first at the base valve with some different sized bleeding shims. But I think that the bleed on the base valve affects more or less only low speed as it is nearly the same as if you would open the clicker some more turns?!? What I was searching for is to get the spike over roots and sharp edges away, without loosing bottoming control (I know it is like searching for the holy grale...). As I reduced the clamping shim of the base valve I wouldn't like to make it any smaller(9,5mm right now - 10mm before). Maybe I will try a lighter mid valve setup at all with less shims.

 

[marcusgunby]

prcucuma i dont think it would make any difference on mid as it lifts over 1mm already before it makes any damping-you would actually make the float less doing it that way and stiffen the damping.

The Wp fork has a large diameter rod and so displaces a reasonable amount of fluid through the base valve.For this reason the bleed shim(on the base valve) works well on that fork.Softening the mid will only help if its actually doing something-with the std lift, changing the mid will do very little as it mostly bleeds off damping-so the base is doing nearly all the damping.

 

[prcucuma]

Thanks for the input! After some tries I might know some more...

 

[marcusgunby]

Let us know how it works out.Good or bad.

 

[tankslapper]

Originally posted by marcusgunby
I rode a set of SXS forks with a similar setup to your suggestion-they were very nice-sadly i only know it had a bleed shim-not the actual stack.

 

this is for the base valve-not the mid which you are refering to-a bleed shim wont work there as it opens a good amount already ie plenty of free bleed.

marcus, the new bladder type forks on the KX250F have a bleed shim on the mid-valve. The nearest shim to the piston is a .10x18 and then goes onto 3x 0.10x24

 

[marcusgunby]

Ive seen that setup alot-i think its more to stop the other shims from overbending and deforming-the YZ has one but it uses a 20.4 thick plate-that wont bend at all and yet the bleed shim wont really work either as the mid lifts over 2mm-why do they put it in is my question???The one place i see it working is on a Cr125 mid-that uses a o ring to preload the stack-the bleed shim will do something in that fork.Talk about extremes-Cr fork with no lift and a YZ with 2mm.

 

[georgieboy]

Marcus, i have the feeling you mix something up. they use a 18.1 shim as being the first in the stack counting from the midvalve piston, to create a bleed, so 18.1 shim isn't covering the ports completely. The shim you rever to is the last shim of the stack.

 

[marcusgunby]

LOL i can see how you think that-however i dont feel that shim is a bleed, as the stack lifts so easily it has bleed already.I feel that shim is like a clamp shim in reverse-it pushes the inside part of the bigger shims-and forces the outside to bend only.This is on a KX KYB-on the YZ KYB they have that plate on both ends of the stack.No stack should have a 20.4 shim.

 

[marcusgunby]

tankslapper did you measure the mid lift on the KXf??