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2004 YZ125 MX to Woods Valve conversion - Input\Comments\Ridicule Wanted

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I apologize for a minor cross-post from my YZ144 thread in the Yamaha sections, but would like to broaden my horizons in regards to the funky things we call boingers on bikes :smashpc: Here is about where I'm at. Been racing my 2004 YZ144 for the past season, and it continues to beat my body up by the 1 hour mark in HareScramble races. I'm aware it's partial personal fatigue, but I know the stock valving sure isn't helping things.

So, since I'm not super well versed in how each shim stack combo will affect things, I've decided to more or less mimic the valving on KTM. I've found stacks for a 2007 KTM 250XC. I've plugged all this stuff into the ReStackor program to see how I can tweak the OEM Shims to match the KTM setup. Here is what I have thus far:

301282_2282123100300_1465516885_3043169_1464109332_n.jpg

~BaseValve~

Stock Stack:

(8) 24 x 0.1

(1) 22 x 0.1

(1) 20 x 0.15

(1) 18 x 0.1

(1) 16 x 0.1

(1) 13 x 0.1

(1) 11 x 0.25

(1) 18 x 0.5

(2) 18 x 1.0

(1) 11 x 0.3

(1) 24 x 0.1

Mod Stack:

(3) 24 x 0.1

(1) 18 x 0.1

(5) 24 x 0.1

(1) 22 x 0.1

(0) 20 x 0.15 REMOVED

(1) 16 x 0.1

(1) 13 x 0.1

(1) 11 x 0.25

(1) 18 x 0.5

(2) 18 x 1.0

(1) 11 x 0.3

(1) 24 x 0.1

That's about where I'm at right now. I have the other 2 valves out, but not torn apart (figuring 1 part at a time right now). If anyone has any input, I'm open to suggestions. Thankfully I have a complete set of parts here to make a valving change, and be able to toss it in the forks with 0 down-time. Makes life a bit easier.

Andrew

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it will be significantly softer , give it a go IMO

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~MidValve Rebound~

Stock Stack:

(8) 27 x 0.1

(1) 12 x 0.1

(1) 26 x 0.1

(1) 24 x 0.1

(1) 20 x 0.1

(1) 16 x 0.1

(1) 14 x 0.1

(1) 12 x 0.1

(3) 11 x 0.25

(1) 20 x 1.6

Mod Stack:

(2) 27 x 0.1

(1) 12 x 0.1

(1) 20 x 0.1

(1) 16 x 0.1

(1) 14 x 0.1

(1) 12 x 0.1

(3) 11 x 0.25

(1) 20 x 1.6

This stack somewhat closely matches the KTM 250XC MidValve Rebound Stack. Not perfect, and from looking at graphs, significantly softer. Eh, not much to lose by trying it :smashpc:

Input?

Andrew

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~MidValve Compression~

Stock Stack:

(1) 16 x 0.1

(1) 20 x 0.38

(3) 27 x 0.1

(1) 24 x 0.1

(1) 20 x 0.1

(1) 16 x 0.1

(3) 14 x 0.3

(1) 25 x 0.4

(1) 11 x 6.0 (spacer)

(1) 11 x 0.2 (Shim)

CUP

Mod Stack:

(2) 27 x 0.1

(1) 24 x 0.1

(1) 20 x 0.1

(2) 16 x 0.1

(2) 14 x 0.3

Suppose it'll be interesting to test out. Gotta swap them on the 2nd leg now. Testing Sunday.

Andrew

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Figured I'd give an update on the fork modification.

Got to take the bike out last weekend. Not the most ideal testing conditions for testing woods setup, but it gave a good indication. So far, all I can say is :smashpc:

I suppose it's a bit screwy that I used KTM suspension as the target, but hey, it is what it is. Go figure that the front end honestly felt like a newer KTM. Bike just felt soft, and gave me confidence. It was too soft for MX, and on the faces of jumps, soaked up too much, but that was expected.

I'm actually quite excited for my next race. Really feeling like the bike isn't going to be fighting me.

Rear shock I went on 15 clicks out on Compression & Rebound damping. HS Compression was 1-3/4 turns out iirc. It could handle having a couple clicks more on rebound damping, but I'll wait until I test in a more woodsy environment.

Andrew

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