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2003 shim stack help

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First off, I am not versed in the exact names of suspension components so please go easy on me. I have a 2003 rm250 (KYB 46U forks) and am looking to get the valving more suited for the woods racing I am trying to get into. I have been riding since 4 yrs of age but just recently raced my first H/S in the vet b class. I finished 8th from last out of 21 in that class. I am 5' 10" 195lbs. I ride in rutted rooty woods with a bit of MX track as part of the course. My bike has the following mods: skid plate, hand guards, 18" rw, rekluse, fatty, 7.0 slide in the cleanly jetted carb. I have the correct springs as the sag is correct.

My problem is the harsh suspension. I am deflecting off everything and it feels as though the bars are getting jerked out of my hands....especially on multiple 4" bumps. I have spent hours adjusting first the fork rebound then compression then shock rebound followed by H/S then low speed compression...only to end up on full open everywhere still getting beat to piss.

I have taken the forks apart and found what appears to be a very stiff shim stack on the base valve?

24.15,6

22.15,2

20.15

20.10

18.15

16.15

13.15

This is not stock according to what I've read. And there is no "peening" over the nut....it doesnt look like ther ever was! I wonder if these are aftermarket bases. I can't seem to get a photo up, but I will keep trying. Also there are no other shims on the rebound side of the valve. Just a 24.40 face shim.

I want to get to plushville. Not concerned with taking on big doubles and such....just soaking up the chop.

I hope I have provided enough info for practical advice from you generous suspension gurus.

Thanks!

Edited by paddymotodaddy

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search the forum for the kyb bladder mod.

 

I think this bike has a bladder fork.

 

Do the mod and post your valving here.

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Alright, these are non bladder forks.

I did a RM 250 02 and it had bladders, so I assumed...

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The previous owner put showa stickers on and me being new to suspension.....well I'm still learning. Again, please bear with me fellas. I'm thinking that I need to set this up closer to stock minus 4 24.15 shims form the stock stack. Any suggestions for using what I have in a better configuration?

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I can provide you the OEM stacks

 

reb

23-0.11*5 13-0.11*1 20-0.11*1 18-0.15*1 16-0.15*1 14-0.15*1 12-0.15*1 10-0.30*3

 

mv

24-0.11*3 22-0.11*1 20-0.11*1 18-0.11*1 16-0.11*1 10-0.30*2 12-0.11*1 14-0.11*1 22-0.40*1

 

base

24-0.15*6 22-0.15*2 18-0.15*2 14-0.15*1 11-0.25*1

 

 

Since I have the EU stacks only there can a difference to the US stock setup.

However, your current basevalve looks very strange. Who the hell uses 2x22.25 shims in a fork?!

 

You should check your mv and reb for changes too!!

Edited by Vietze

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So I've been searchin and tinkerin and need help disassembling my cartridges. These have no little dents to drill out. I have tried enough heat to be too hot to touch but not discolor anything and cannot loosen the cap. I'm not even sure if it is a threaded cap...

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Thanks for those numbers,Vietze!

 

Here's what I have, hopefully I'm conveying this correctly:

 

reb:

 

23.11*4

21.11

15.11

10.11

16.15

14.15

12.30*4

16.1.60 washer

nut

 

MV:

24.11*3

22.11

20.11

18.11

16.11

10.30*2

12.11

14.11

22.4

spring washer

collar

cup washer

 

and just so you don't have to look back at previous info, the base:

 

21.15*6

22.15*2

20.15

20.10

18.15

16.15

13.15

 

So, according to Vietze its close to stock except the bv stack.

 

rider=195lbs and gaining everyday my forks are apart!

vet B hare scrambles in WI & MN

2003 rm250 KYB 46mm open chamber, no bladder

sag is correct

the bike deflects off everything.  blows through corners.  kicks my ass.

 

I realize all riders are different and have different expectations so I'm just looking for some experienced advice on where to start in order to get this bike happier in the woods.  I am willing to put the time in fine tuning everything, but since this is my first crack at modifying valve stacks, I was hoping you guys would offer some wisdom in getting a good starting point.  Sorry about jumping the gun and posting before I had all of the info!!!!!!!

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Dude, your rebound is totally messed up....

Get the shims to put the OEM reb stack in there.

 

Float would be interessting on your mv. But as you said, this one looks like stock.

 

Changing the 24.15 and 22.15 to 24.1 and 22.1 will make a big difference! I would go for that with the OEM reb and mv for the first try.

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I want to try experimenting with the shims I have if that's feasible. Any opinions of this set up:

Reb,

23.11*4

12.3

20.11

18.11

16.11

15.11

14.11

12.3*2

10.1

MV

Stock

Base,

24.15*2

22.12

20.13

18.11

16.15

13.15

11.25

I know its best to change 1 thing at a time but I figured the reb was pretty chooched as it was and I'm confident stock compression setup is going to be too harsh. Am i way out trying this setup? Thoughts?

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O.k. An update.......finally. After time testing and measuring I realized that the bike was under-sprung for me. I scored the correct rate springs on amazon for $83 each end. A great price on new springs but the seller, power sport superstore messed up and only sent the shock spring.

So it took about 2 weeks to get the fork springs and during that time I serviced the rear and steering bearings and figured since I couldn't ride anyway, I would address the small trans leak. It was coming from the inner clutch cover. When I pulled this off, I found that the little arm that actuates the power valve had broken where it contacts the governor. .....Shatty..... that part is supposed to arrive Monday. I have since installed the new fork springs and changed the shims. While I was at it, the forks also received bushes and seals. The best deal was the KYB o.e. kit from the local stealer! And actually he's a Yam-Hon stealer so they came in a Yamabox.

1 of the fork old springs was curved like a banana and both were about 4mm shorter that the new springs. Is that because they were that sacked out or are racetech springs often longer than stock?

The rebound is back to the stock stack. I will post the other changes once I get a chance to ride and evaluate. I appreciate the help I've received on here! I also have been talking with a tuner and will elaborate more when I know I'm not screwing up good advice.

O.k. An update.......finally. After time testing and measuring I realized that the bike was under-sprung for me. I scored the correct rate springs on amazon for $83 each end. A great price on new springs but the seller, power sport superstore messed up and only sent the shock spring.

So it took about 2 weeks to get the fork springs and during that time I serviced the rear and steering bearings and figured since I couldn't ride anyway, I would address the small trans leak. It was coming from the inner clutch cover. When I pulled this off, I found that the little arm that actuates the power valve had broken where it contacts the governor. .....Shatty..... that part is supposed to arrive Monday. I have since installed the new fork springs and changed the shims. While I was at it, the forks also received bushes and seals. The best deal was the KYB o.e. kit from the local stealer! And actually he's a Yam-Hon stealer so they came in a Yamabox.

1 of the fork old springs was curved like a banana and both were about 4mm shorter that the new springs. Is that because they were that sacked out or are racetech springs often longer than stock?

The rebound is back to the stock stack. I will post the other changes once I get a chance to ride and evaluate. I appreciate the help I've received on here! I also have been talking with a tuner and will elaborate more when I know I'm not screwing up good advice.

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