Shim stack help

Questions and comments about converting to beefier forks..
User avatar
krazyinski
Member
Posts: 461
Joined: 12:26 pm Mar 10 2006
Country:
Location: San Antonio Texas

Post by krazyinski »

hell I wish could send my suspenders off to MX-Tech and get them worked over, but my wife refuses to sell one of the kids.
2000 KDX220 FRP Ported,plated cylinder,milled head, FRP bored carb, V force 3 reeds, FMF desert pipe, 10oz FWW, 98 KX forks and oem shock re valved by Pro Action, hyd clutch, fastway pegs, tall seat foam, gripper cover, 29" CRhigh mini bars, Cycra brush gaurds.
User avatar
bradf
Gold Member
Gold Member
Posts: 703
Joined: 02:17 am Dec 11 2004
Country: USA
Location: Anderson, SC

Post by bradf »

Vince, I e-mailed you the word doc of my set-up.
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
User avatar
krazyinski
Member
Posts: 461
Joined: 12:26 pm Mar 10 2006
Country:
Location: San Antonio Texas

Post by krazyinski »

so are you afraid to share with every one else?
2000 KDX220 FRP Ported,plated cylinder,milled head, FRP bored carb, V force 3 reeds, FMF desert pipe, 10oz FWW, 98 KX forks and oem shock re valved by Pro Action, hyd clutch, fastway pegs, tall seat foam, gripper cover, 29" CRhigh mini bars, Cycra brush gaurds.
User avatar
bradf
Gold Member
Gold Member
Posts: 703
Joined: 02:17 am Dec 11 2004
Country: USA
Location: Anderson, SC

Post by bradf »

Gimmie your e-mail addy. My valving is good for 99-02's that have mid-valves. If yours has a check plate (CV) then that is a difference that will have to made up by adjusting CV lift. Also mine had a bladder and I did a simple yet very affective mod to eliminate it and the restrictive barrier's function.
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
User avatar
krazyinski
Member
Posts: 461
Joined: 12:26 pm Mar 10 2006
Country:
Location: San Antonio Texas

Post by krazyinski »

mine are 98's do you have the set up for what was done to the showa? i have a 2001 showa I am going to use. email krazyinski@hotmail.com
2000 KDX220 FRP Ported,plated cylinder,milled head, FRP bored carb, V force 3 reeds, FMF desert pipe, 10oz FWW, 98 KX forks and oem shock re valved by Pro Action, hyd clutch, fastway pegs, tall seat foam, gripper cover, 29" CRhigh mini bars, Cycra brush gaurds.
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

Thanks Brad.
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
User avatar
krazyinski
Member
Posts: 461
Joined: 12:26 pm Mar 10 2006
Country:
Location: San Antonio Texas

Post by krazyinski »

Thanks Brad. your base valve shim stack is close to mine except I have only (3) 24's the rest I have yet to investigate. I did have (4) 24's but removed one trying to get a better ride out of the forks with the .43 springs. now with the .40 all is well.
2000 KDX220 FRP Ported,plated cylinder,milled head, FRP bored carb, V force 3 reeds, FMF desert pipe, 10oz FWW, 98 KX forks and oem shock re valved by Pro Action, hyd clutch, fastway pegs, tall seat foam, gripper cover, 29" CRhigh mini bars, Cycra brush gaurds.
User avatar
bradf
Gold Member
Gold Member
Posts: 703
Joined: 02:17 am Dec 11 2004
Country: USA
Location: Anderson, SC

Post by bradf »

Your BV stack is "mostly" LSC, but it does affect HSC. Your CV lift is critical in what you feel in the mid-stroke of HSC.
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
User avatar
krazyinski
Member
Posts: 461
Joined: 12:26 pm Mar 10 2006
Country:
Location: San Antonio Texas

Post by krazyinski »

I can feel the differance in the mid stroke the next seal change I will investigate the CV lift. after Xmas I can get the rear shock done.
2000 KDX220 FRP Ported,plated cylinder,milled head, FRP bored carb, V force 3 reeds, FMF desert pipe, 10oz FWW, 98 KX forks and oem shock re valved by Pro Action, hyd clutch, fastway pegs, tall seat foam, gripper cover, 29" CRhigh mini bars, Cycra brush gaurds.
User avatar
Colorado Mike
Gold Member
Gold Member
Posts: 1921
Joined: 11:42 am Feb 25 2005
Country:
Location: Colorado

Post by Colorado Mike »

Is there any info available regarding the mid valve? I have '03 KX forks, and am not clear on the wear the mid valve even is. I need to learn up on this stuff.
Mike

Life's tough, it's even tougher if you're stupid.
'04 KDX220
User avatar
bradf
Gold Member
Gold Member
Posts: 703
Joined: 02:17 am Dec 11 2004
Country: USA
Location: Anderson, SC

Post by bradf »

CM, your CV is on the end of the rod. The midvalve circuit is located directly behind the piston or opposite side of the piston than where the nut is. The CV is like a digressive dampning device. Instead of controlling flow with shims it simply uses a spring behind a spacer/washer to open when enough pressure is present. It is an ON/OFF circuit. The higher the lift (amount of travel the spring allows washer to slide open to allow oil flow) the lower the HS dampning affect is. Your lift would normally be about 1.3 mm. I think that 03's had a 2 stage MV stack as well.
'04 220 w/'01 KX250 USD forks, '02 RM125 Showa shock, Rekluse EXP 3.0, LHRB & all RB'd
User avatar
80elkster
Supporting Member II
Supporting Member II
Posts: 135
Joined: 08:43 pm Jan 01 2006
Country:
Location: Maple Valley WA

Post by 80elkster »

Has anyone tried Brad's setup yet? I'm about to on my son's 99 KX250 forks, but what I need to know is do we need additional shims for the midvalve setup? I don't know what shims are present on the midvalve and if we need to add some. Brad please help me out here. :grin:
06 DR650 Farkled
91 WR250 2T
00 300EXC (Sold)
79 XS850 (Sold)
79 CR250 (Sold)
78 IT400 (Stolen)
75 G5 100 Kawi (Gave it away)
73 F7 175 Kawi (Sold)
70 175 Brigestone (Recycled)
05 KDX200(Son's)
93 KDX200
75 KT250 Trials
250 Quads
Just glad to be ridin!
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

Shims ARE spendy. That's the main reason I haven't replaced all of mine..which happen to be 15s (.15mm/.006"). The 10s (.10mm/.004") seem to be the choice of most.

CM...I thought you commented on bradf's posted animation. You didn't see it?

There are a couple of things that are not right. Honestly, I did not study every word said...maybe I missed it.

Here goes a few:

Re: Can't see the stack.

Answer: In the picture, the silver line under the gold part.

Yes. Part of it. The compression stack (of the base valve, naturally). This can be single or double stacked. In your case it's a double stack because you have two 'cones', right?

Bradf said (paraphrase), The shim closest to the piston has to cover the holes.

CM said, 'Brad, the check valve washer I have completely covers the holes in the GV'

You guys are talking about two different things, there. Brad the 'closest SHIM'..and I believe he's referring to the shim stack...I mean, he SAID shim.. CM..you are talking about the check valve which in your configuration is on the rebound side of the piston.

DO your 21s cover the holes on the piston?

Check this:

Image

Notice the brass-colored spring loaded thing sitting on top of my piston? Same sort of deal.


Bradf's is the same way. I''m saying, he doesn't have a stack of shims on the top side of the piston, either. He has a spring/washer/sleeve for his checkvalve portion.

OK...so that's all good, right?

Your low speed setup is odd, because there is no taper to it at all. Simply a stack of 5x21s and then the 12 which is a transition shim, separating the two stacks.


Where you will find the rebound stack (if it's there) is on top of the midvalve piston. Obviously, the rebound stack is upside down from the compression stack...in each case the widest starting shim is against the piston, in each case that shim has to cover the piston ports to be doing anything.

CM: If you end up ordering a pile of shims (and they are going to be .10mm), please keep me in mind. I will split the cost of the mess with you if that works to your advantage. You can see my stack in my bike profile..basically I would want to start at least with .10s to replace my .15s.

Any of this make any more sense than you had before? Less?

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

Whether you need more shims or not of course depends on what you have.

Bradfs setup is something like 36 shims per leg. There is re/comp and LSC/HSC for both on the midvalve.

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
Post Reply