Revalving a Factory Connection KYB SSS Revalve

[C-P]

Just acquired a set of 07 YZ250F SSS forks that are being swapped onto my 03 YZ250.  Similar to what NitrousR1 was doing last year, so basically copying some of the stuff he posted.  Didn't bother to ride them yet, they needed seals, and well next thing you know I've got all the valving apart...previous owner claims FC revalved them, the stickers were present of course, and the valve stem peening was removed, so...It appears the changes were pretty minor and have no idea for what purpose they were built - here's what I have (and my guess as to what was modified)

 

Base Valve:  (all stock?)

 

32.12 (X17)

30.12

28.12

26.12

24.12

22.12

20.12

18.12

15.12

14.25

14.25

20x1.6 washer X2

11.25

-looks like these were no bleed from the factory...? 

 

 

Mid Valve:

 

20.12 (X3) ----"Maybe" they pulled one 20 here? 

18.12

16.12

14.12

11.30 (x2)

17.30 (x2)

 

about .5mm float to my best measure ability

 

Rebound

 

20.12 (x3)

13.12

20.12 ----This was added? 

18.12

16.12

14.12

10.25 (X2)

16x1.5 washer

 

I'm a decent mid pack B woods rider, so my thoughts for starting points:

 

-Go to 12-13 face shims on the base valve

 

-Leave mid alone

 

-remove that extra 20 from the rebound. 

 

-Also have a 1.7 IC spring for it. 

 

I guess my 2 questions would be:

 

-X-over or no X-over?   Am going to the softer IC spring, and there appears to be no bleed shim setup, so not sure if I need it.  If I did one, it would be around 6th or 7th face shim, I've got an extra 22 I can use. 

 

-Do I go any softer on the rebound, and pull out one of the face shims?  I'm already taking out that extra 20, I know some folks recommend lightening up the rebound for the woods. 

 

As usual, thanks in advance!!! 

[kan3]

That's stock mid on 2007 forks. If the previous owner paid for a revalve then he really didn't get one. Stock base, stock mid and they moved 1 shim around on the rebound. I'd just do what you suggested and ride it for a bit. You'll probably find you'll like it if you're B pack enduro rider.

[NitrousR1]

Some of the factory connection revalves I've taken apart have been only a shim or two different from stock valving.

They seem to make small changes and try one thing at a time. Usually not enough changes for a regular rider to notice.

I get there theory but when you ride your new revalved suspension and you still have the same issues id feel ripped off.

[C-P]

Ok, so I'm just debating the mid at this point. Assuming that it's stock, and remeasuring the other mid, float is probably closer to .35. So, I could remove one of the face shims. But would that be too light of a stack? As it is, the 250F mid was shimmed way lighter than the 250 2T by Yamaha. According to valving logic, the 250 2t had five 20s for face shims.

[kan3]

I don't believe that's correct.  As far as I know the 125/250/250f all used that mid stack for 2007.

[Kyle Tarry]

If you want to open up the float a bit, I'd probably space the piston out rather than removing a face shim.

 

On those forks 0.4-0.5 should be pretty plush.

[C-P]

I don't believe that's correct. As far as I know the 125/250/250f all used that mid stack for 2007.

Yeah, my bad. It's the rebound that looks to be a bit stiffer on the 2T.  And only by 1 face shim.  Getting dizzy reading all these valving charts!  Considering Kyle's advice, I may go back to plan A, leave the mid alone for now and if I feel like I need to open it up, get the correct shims to space it out a bit.   

Edited May 31, 2014 by C-P

[Piney Woods]

Some of the factory connection revalves I've taken apart have been only a shim or two different from stock valving.

They seem to make small changes and try one thing at a time. Usually not enough changes for a regular rider to notice.

I get there theory but when you ride your new revalved suspension and you still have the same issues id feel ripped off.

Not just FC. I think a lot of this goes on.

[C-P]

Got er all done, swapping parts between 3 bikes and finally ready ride, then it poured all weekend! Didn't want to test and tune in the mud, gotta wait till Wednesday.

[C-P]

Got to ride these things yesterday and was impressed right out of the box. They feel much more controlled and tunable with the clickers than my OC.

I did leave the mid valve alone, just pulled 4 face shims from the base, 1 from rebound and put in the 1.7 ICS. The springs are a bit soft for my weight, and I started with 300ml in the outer chamber, so I think any harshness I felt was from getting close to bottoming - used all but about 2 inches of travel in woods riding.

Think I've got about 90% of what I want from them as it is. Good stuff!

[C-P]

Ok, mid-season ride report, maybe time for some fine tuning, looking for a little direction:

 

Did the changes mentioned above and went to .47 springs for my weight.  Have ridden 1 hare scramble and 1 enduro, as well as covering the variety of terrain we see here.   They're definitely better in faster open harescramble stuff than enduro.  They take high speed hits great, but get pretty busy in the smaller choppy stuff.  Our last enduro here was super tight, volleyball-size rocks half-buried in the trail everywhere, with a nice coating of greasy mud.  Never used more than 1/2 the stroke the whole day.  Thinking I have a couple options.

 

-Add a X-over in the base.  If so, what size would be ideal? 

 

-Add float to the mid.  Does this affect rock riding compliance?  I don't know. 

 

Would it be crazy to do both at once?  Or, what should I try first?  Thanks! 

[Hans Schmid]

How heavy are you to be adding 47s in the front?

[Kyle Tarry]

Would be helpful if you posted exactly what you are running now, there is some variation in the comments above.

 

I'd probably try a crossover on the base.  Maybe 20 x 0.1, between the face shims and HSS.

 

It's unclear what the float actually is, I'd probably try it around 0.4 mm.  If you continue to not use full travel, maybe open it up a bit, after trying the base valve mods.

 

I agree with Monk's question.  I am 175 lb and run 0.44s on my WR (OC KYB).

[C-P]

Monk - to answer your question - Heavy!  215lbs without gear.  Now you're gonna say I need to heavier springs...

 

My stacks are currently:

 

BASE

 

32.12 (X13)

30.12

28.12

26.12

24.12

22.12

20.12

18.12

15.12

14.25

14.25

20x1.6 washer X2

11.25

 

STOCK MID

 

REBOUND

 

20.12 (x3)

13.12

18.12

16.12

14.12

10.25 (X2)

16x1.5 washer

 

Since my mid is stock, I'd figure float at .35 and any variance being my poor ability to measure. 

 

My plan is to order up some shims to use as crossover and to add float for the mid so I have both available, while I figure what the next move is. 

[Hans Schmid]

Nope, I'm 220 with 47s.... I was just curious...

[mog]

Yes you should consider taking one shim from the mid and adding a cross over , or it will never use much travel

What oil amount do you use ?

[C-P]

Yes you should consider taking one shim from the mid and adding a cross over , or it will never use much travel

What oil amount do you use ?

I'm probably splitting hairs here, but would it be better to remove 1 face shim from the mid, or keep the shims I have and add a .1 under the collar?

 

On the crossover, how far in should I go, like 8-10 shims? 

 

I currently run 300ml in the outer chamber, so my thinking is that I have plenty of room to add oil there if I need help with bottoming resistance.  I can get pretty close to bottoming now if I'm really hauling and hit stuff hard, like big trail whoops and things. 

 

Thanks! 

[NitrousR1]

Id remove a 20.1 from the mid. I have nearly the same fork valving as you plus 1 mid face shim removed. I have 4" travel left, so id imagine you have a lot of travel left.

Next I'm thinking of pulling one of the 17.3's and shimming to get float .35mm or running a crossover on the base valve. Maybe 22 or 24.1.

[C-P]

Id remove a 20.1 from the mid. I have nearly the same fork valving as you plus 1 mid face shim removed. I have 4" travel left, so id imagine you have a lot of travel left.

Next I'm thinking of pulling one of the 17.3's and shimming to get float .35mm or running a crossover on the base valve. Maybe 22 or 24.1.

Roger that.  I might as well start with the mid.  If I'm still looking for more, the base is a couple less steps to access the next time around. 

 

The one thing I didn't really try last Sunday, and probably should have, was cranking my comp adjuster way out - I was running at my usual 13 clicks - not sure if backing out to 16 - 18 would do anything for the rocky stuff?

[mog]

It would help , I would remove a 20.1 from the mid and add the cross 8 shims down