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Shim stack help! 2009 CRF250R. 166lbs, 6"2, sand

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Hey suspension experts,

I need some help dialing in my suspension because I have revalved it a twice already but don't know what to do now...

My details are the following:

BIKE: Honda CRF250R 2009, Showa suspension

SPEED: Fast C Grade

WEIGHT: 166lbs or 75kgs without gear. (apparently I'm on the border line to get stiffer springs but not sure if I need them?)

HEIGHT: 188cm or 6"2' (I am quite tall for a 250F and feel way too big for it)

I am in Perth, Western Australia and I ride mostly sand motocross. The track has a limestone base and deep sand on top. Most of the track is whooped out and gets very rough. It also has braking and accelerating bumps everywhere. The jump faces are limestone and some sections of the track are quite hard, rocky and have square edges.

I'd like to setup my LSC suspension for the deep sand whoops because thats what most of the track is and get my HSC to work with the braking bumps and square edges where it is more hardpack. The outside lines on the corners are always whooped out and you normally have to stand up going around the outside.

I see the local pro's sitting down on these corners and make it look very easy. But when I try to do it they just beat me up!

I have my LSC at a comfortable setting for now, but my HSC feels way too hard and needs to get softened up I think. Because coming into corners at speed it is unstable and deflects off the braking bumps instead of soaking them up. My rebound is quite soft I guess, because I feel like it turns better and alot more comfortable. At the moment I want to fix up my HSC on my forks and make the LSC more compliant with the terrain, so that it compresses and rebounds the same speed as the bumps.

What is the best way to do this? Will adding thicker shims help by replacing the 0.1mm shims with 0.15mm ones?

SHIM STACKS:

FORKS:

Springs: 0.46kg (haven't measured them, but I researched and found this as stock)

Oil outer chamber volume: 350cc (I started with 320cc and added 5cc until it stopped bottoming)

Oil height from fork cap: 140mm. (Inner chamber after being bled)

Oil Type: Motul Factory Line 5wt

COMP: 12

REB: 12

FLOAT: Im not sure what my float is because I haven't tried to measure it yet and only learning now how to do it... But I'm still confused

SHIM STACKS:

BASE VALVE:

25 X 31 X 0.1

1 X 29 X 0.1

1 X 27 X 0.1

1 X 25 X 0.1

1 X 24 X 0.1

1 X 23 X 0.1

1 X 22 X 0.1

1 X 21 X 0.1

1 X 20 X 0.1

1 X 19 X 0.1

1 X 18 X 0.1

1 X 17 X 0.1

3 X 16 X 0.1

1 X 16 X 0.3

MID VALVE:

REBOUND:

3 X 19 X 0.1

1 X 18 X 0.1

1 X 17 X 0.1

1 X 15 X 0.1

1 X 13 X 0.1

2 X 9 X 0.1

2 X 16 X 0.3

COMPRESSION:

4 X 20 X 0.08

2 X 18 X 0.08

^ are these compression shims on the mid valve supposed to be the 20's against the valve or the 18's againts the valve?

SHOCK:

SRPINGS: 5.3kg/mm (haven't measured them, but I researched and found this as stock)

RACE SAG: 100 - 105mm

COMPRESSION: 12

REBOUND: 7

HiSC: 4 full turns out from full closed. (All the way out CCW (soft)) I DO NOT have the FC HiSC spring.

NITROGEN: 150psi. (By my understanding the nitrogen is like the oil in the outer chamber in the forks and controls bottoming resistance... Is this correct???) Should I be around 170psi???

SHIM STACK:

COMPRESSION:

YSS VALVE

1 X 38 X 0.2

2 X 36 X 0.2

1 X 34 X 0.25

1 X 26 X 0.25

1 X 32 X 0.25

1 X 30 X 0.25

1 X 28 X 0.25

1 X 24 X 0.2

2 X 17 X 0.2

6 X 25.25 X 0.6 (thick pivot shims)

1 X 22 X 0.3

1 X 24 X 0.25

1 X 26 X 0.25

1 X 27 X 0.25

1 X 28 X 0.2

1 X 28 X 0.25

1 X 28 X 0.3

1 X 30 X 0.25

1 X 30 X 0.3

1 X 32 X 0.25

1 X 32 X 0.3

1 X 34 X 0.25

1 X 36 X 0.25

1 X 38 X 0.25

2 X 40 X 0.2

1 X 42 X 0.25

2 X 44 X 0.2

8 X 44 X 0.25

1 X 44.5 X 5.0

1 X 44 X 0.3

REBOUND:

2 X 36 X 0.2

1 X 28 X 0.1

1 X 34 X 0.2

1 X 30 X 0.2

1 X 26 X 0.2

1 X 17 X 0.2

I don't have alot of shims to play around with, only the ones I have in there. I will buy some shims soon when I know which ones I will need.

I do have the full version of the shim restackor program if that helps at all, but I haven't had the time to learn how to use it!!! As i find it very confusing!

How does the amount of oil in the inner chamber affect the suspension???... I have changed it a few times and found that it makes the top part of the stroke harder (more oil) or softer (less oil). Is this right?

I'm happy with my shock for now, because I just want to get my forks dialed in and then start messing with the shock later.

Please excuse me if anything sounds wrong... as I am still learning! and I hope I haven't left out any info.

Thanks for your help in advance! :smirk:

Fishdog

:smirk:

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the rebound stack on shock makes no sence , it should have 40mm shims and loads more of them

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ok thanks no hand! that's what I thought :smirk:

Mog, I have a YSS aftermarket valve in there and that is why there is a 38mm shim against the valve. There is a recess all around it which makes the 38, the biggest shim to fit on it without overlapping over the edge.

Does my fork stack look good?

Do I have too many LSC (25x31x0.1) shims???

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ok thanks no hand! that's what I thought :smirk:

Mog, I have a YSS aftermarket valve in there and that is why there is a 38mm shim against the valve. There is a recess all around it which makes the 38, the biggest shim to fit on it without overlapping over the edge.

Does my fork stack look good?

Do I have too many LSC (25x31x0.1) shims???

Looks like to much LCS to me. I'd remove a couples of face shims there:ride:.

Mr P

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what float does it have? you cant access the base stack without knowing the float.Its the amount of movement the face shim on the mid can move off the piston face.

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