WP43 shim stack modification

[Chouca]

After a few tries I´ve found a compression stack that work very well for woods riding on my 200EXC-00. When I bought the bike it did not use all the stroke, it NEVER bottomed. I have now lightened up the stack both in low and high speed and now it is much better.

My shim stack;
2)24 x.1
1)22x.1
1)12 x.15
1)20 x.1
1)18 X.1
1)16 x.1
1)14 x.1
1)12 x.1
1)12 x.15
1)18 x.2

 

[marcusgunby]

I ran something similar on my sx(expert level mx riding!!).Makes you wonder why they come so stiff.

 

[dbrace]

No offence but that is so soft. What midvalve were u guys running, springs etc.

 

[marcusgunby]

dbrace i never said it worked well-just thats what i ran;)

 

[Chouca]

I have not explored or touched the midvalve so (I guess) it is stock. How does a standard midvalve look, what possibilities are there for adjustments and what are the consequences... The fork is MUCH better after this change, can some midvalve magic improve it further I´m all ears!

 

[svi]

Originally posted by marcusgunby
dbrace i never said it worked well-just thats what i ran;)

Marcus,
That's the funniest reply I've seen in a long time!

 

[marcusgunby]

svi i jest:) it wasnt that bad like Chouca said, alot better than std.
Chouca if you manage to get to see a KYB or showa midvalve you will see a big difference to the WP.Wp uses alot of lift and the stack is not very progressive.Its not much different to a checkplate of old.

 

[Chouca]

So Marcus,

Originally posted by Chouca
How does a standard midvalve look, what possibilities are there for adjustments and what are the consequences...

As You understand I have not taken the WP43 midvalve apart - butI guess it won´t be long...

 

[marcusgunby]

Std midvalve is something like
24.1(4 of)
and then a 16mm plate i seem to remember-so the 16mm plate acts like a clamp shim.

 

[Chouca]

Thanks Marcus,

I spent last night going through a bunch of DRN-posts trying to understand how everything fits together and I now believe I start to see the role of the midvalve.

JER stated in a post that;
"The WP's have one of the softest midvalves curently on any bike.. Thats the problem with them.. They use too much base-valve."

If I understand him right stiffening up the midvalve with less float (by thicker clamping shim or what???) and more 24mm shims, or a stack with different sized shims will help the base valve to do a better job!?

Does this make sense???

 

[marcusgunby]

Yes totally.jer has put some good info about the role of the midvalve in the midvalve thread.Its the key to good fork performance.Its a shame Wp hasnt really understood the midvalve as yet.Cant think why they keep altering the forks with trick coatings and bushes but dont just apply a bit of good valving.its not that hard for Wp - just strip down some good KYBs and Showas and look why they work better.The main difference on the wp is the 14mm damper rod but that doesnt mean they cant get a good stack.

 

[jossbuk]

Has anybody looked at the 2003 Husaberg parts list. They now specify 20.1, 22.1 and 24.1x4 mid valve shims(check valves). I did not figure out the lift or the stopper plate... Are the 2003 KTM's the same

 

[jossbuk]

I am being dull... Do the 48 WP fron forks push more oil through the mid valve than the 43's even though the cartridge is the same diameter?

 

[Chouca]

Hmmm,

Originally posted by jossbuk
They now specify 20.1, 22.1 and 24.1x4 mid valve shims(check valves). I did not figure out the lift or the stopper plate...

I guess the same midvalve stack on a WP43 will stiffen up the midvalve a bit, and be a step in the right direction!?

What can then be done to get less float in addition to this stiffer stack?

 

[marcusgunby]

A nice 0.5mm thick washer or some more 0.1mm shims stacked ontop of each other.

 

[Chouca]

Thanks guys,

I have learned a lot and look forward to try to do some changes and see how I can further improve the forks!