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View Results: Would you consider participating in a group buy?
Yes, if the price is right. 13 86.67%
No, these cartridges are way to expensive. 0 0%
No, USD forks will work so much better 2 13.33%
Voters: 15. You may not vote on this poll

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Old 12-17-2012, 09:19 PM   #811
Kokopelli OP
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Well, something is very wrong. I rode down a curb and it bottomed out. I can also hear a bit of noise when moving the forks up and down. Could be from the brakes, though.

This is what I did, let me know if you can pick where I screwed up.
  1. removed the fork legs
  2. separated stanchion from sliding tube
  3. removed all the internals
  4. installed new fork seals
  5. inserted stanchion into the slider
  6. installed cartridge
  7. tightened the allenhead nut at the bottom of the slider to 40nm (well, one of them)
  8. installed the fork legs back into the triple clamp
  9. poured in 430cc into each fork leg
  10. pumped the slider until there were no more bubbles
  11. inserted the spring and spacer
  12. added the top cap
  13. compressed the spring so I could counter lock the nut to the top cap
  14. wound the top cap into the stanchion
  15. Installed the fork brace, front brake and front wheel, torqued to specs
  16. went for a ride down the drive
  17. had puzzled look on face ever since

So know I am a bit screwed, because I need the bike by the 1st of Jan. Hopefully, I haven't damaged anything.

I measure 252mm from the top of the fork slider (just below the dust cap) to the bottom of the triple clamp, with the forks extended.
With the weight of the bike it's 207mm
With me on it, it's 189mm.

I now have 5 ring showing, before it was three.

As you've probably figured out by now, I have no idea what those figures should be. Does this mean I have 63mm sag?


Does this sound about right?

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Kokopelli screwed with this post 12-17-2012 at 10:19 PM
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Old 12-17-2012, 10:44 PM   #812
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How hard was it to get the top cap into the stanchion?

Generally you want a bit preload on the spring , and usually this involves compressing the spring around 1/2 " before the top cap starts screwing into the stanchion.
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Old 12-17-2012, 11:09 PM   #813
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There was no pressure on the top cap. I had the preload backed out all the way. Would you expect to be any with this arrangement?
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Old 12-18-2012, 05:09 AM   #814
Renner
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Quote:
Originally Posted by Kokopelli View Post
13. compressed the spring so I could counter lock the nut to the top cap
I wonder... roughly how many screw threads were showing under the counter-lock nut? 3 or so?
Were the top cap adjustments even with the top before running the top cap down the damper rod's threads?
My soft-spring set-up needed the extra 10mm spacing to bring the preload adjustment down. That's with a "light" R80ST and me at about 215 lbs.

I'd suggest adjusting the oil level at 120mm air gap rather than by ml or cc quantity.
That's 120mm with the spring out, forks fully compressed (after tieing forward the centerstand and pulling the front down, kneeling the bike).

Like this but with the cartridge assembly (minus spring) installed.

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Old 12-18-2012, 06:44 AM   #815
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I thought hte instructions said let there be three rings showing, and back the central screw out 1.5 times when installing the top cap? That would allow the central damper rod to be in the right place...

WHen Ibined mine up the first time, and I experienced clunking it was because the rod had come unscrewed from the top cap (while I was fiddling with the preloadadjuster) so just double check that thats not hte case.


189 is to 252 as 19 is to 25, that roughly 1/3, actually a little less, so youre between 25 and 30% sagged, which sounds ok, could be a little more. I think I was down around 170-75. The Germans said that was ok, even though it looked like a lot. Its been ok.


THe preload adjuster I am less impressed with. It will only get you very small adjustments in preload. Like, the diff between 170 and 175 mm, or 185 and 190mm. Its for very small adjustments to preload, which I felt it too fine a resolution for me to notice, but I am a hamfist.
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Old 12-18-2012, 07:08 AM   #816
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Quote:
Originally Posted by Stagehand View Post
I thought hte instructions said let there be three rings showing, and back the central screw out 1.5 times when installing the top cap? That would allow the central damper rod to be in the right place...
I like having the maximum amount of thread engagement with the top cap to the plunger rod.
To do this I screw in the top’s preload adjuster all the way, which unloads the spring setting for ease of assembly.
After all is together then setting 3 rigs at the preload adjuster is probably a reasonable starting point.

The small, damper adjustment screw I keep flush with the preload adjuster top during assembly.
When spinning the top cap onto the plunger rod, the damper adjuster is what bottoms-out… on the damper adjuster rod.
so those two (preload & damper adjusters) are what limit the ‘top nut to plunger thread engagement’ and control the extended length of the fork legs… as in topping-out…
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Old 12-18-2012, 07:52 AM   #817
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I found the 4.8 springs to be quite soft, but springs I had before were very firm and good for the road. The 4.8's w/ the 25mm spacer I had issues with bottoming out even with 1/3 travel for preload, ended up using a 35mm spacer. It's better with it. also HH Race tech sent me 5.8 springs and spacers (20mm and 35mm). I never used the 5.8 as I felt it wold be to firm. I don't think it bottoms out with the 35mm spacer.

I agree with Stage the preload does very little, the comp and rebound adjustments are noticeable.

Here's the link on some of my notes to springs and spacers.
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Old 12-18-2012, 08:44 AM   #818
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Renner- I am kind of rememebring doing this, and yeah I think you are right-- the preload adjuster ran in, or whatever way unloads it. I recall trying to do it incorrectly at one point (I mean one of the many points, thankfully not all in a row) and it turns out when i installed the top cap, I couldnt get any rebound adjust.
Something like that. Man it was over six months ago already. I'm lucky I can rememebr anything about 6 months ago at all
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Old 12-18-2012, 08:57 AM   #819
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I know with the 35 mm spacer, it takes some amount of pressure on the spring to get it down so you can get a wrench on the 13mm (?) nut below the cap. But if doing it right the spring will hang on the nut just long enough to get the wrench on it. Make sure the top cap bottoms out on the threaded rod, then tighten the nut up to the cap and lock it in place.

If you used a string to pull the rod up, just tie half a knot, and pull it free once things are tight.

The 4.8 springs are soft though. yeah i was bottoming out w/ the 25 mm spacer.

Thread the preload out to increase preload. Preload threaded all the way in is lighter pressure on the spring.
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Old 12-18-2012, 09:56 AM   #820
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Thanks for all the replies. I just got up and was hoping that someone had responded.

The only thing I can see that may have done wrong, is the oil level (filled on quantity)

Before I'll take it all apart again I'll try riding it one more time. The reason it bottomed out may have to do with the rebound adjustment. Maybe the suspension just kept on packing down until it bottomed out.

What's the consensus on the slider tube bolt? How can I get that to tighten properly?

I guess I'll start cleaning my work area first. I am a messy worker and accumulate a lot of tools around me.
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Old 12-18-2012, 10:51 AM   #821
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Quote:
Originally Posted by Kokopelli View Post
What's the consensus on the slider tube bolt? How can I get that to tighten properly?
oh yeah...

I'd load the suspension and try torqueing it again.
If you further compress the spring internally it will help to keep the cartridge from spinning while you tighten the bolt.

a couple tie-down straps to a pallet under the front wheel or something...
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Old 12-18-2012, 11:28 AM   #822
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I've double checked my sag numbers. With 5 rings showing I have a sag of 56mm. That's not a lot. So if there is any bottoming out, it related to the compression and rebound adjustments. Is that assumption correct? I am still trying to get my head around these adjustments. The instructions mention 3.5 turns, but from what I could tell, that's lock to lock. Does turning clockwise increase the damping or reduce it?

I don't really want to pull the thing apart again, unless I am sure that it needs to be done.
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Old 12-18-2012, 12:12 PM   #823
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Quote:
Originally Posted by Kokopelli View Post
I've double checked my sag numbers. With 5 rings showing I have a sag of 56mm. That's not a lot. So if there is any bottoming out, it related to the compression and rebound adjustments. Is that assumption correct? I am still trying to get my head around these adjustments. The instructions mention 3.5 turns, but from what I could tell, that's lock to lock. Does turning clockwise increase the damping or reduce it?

I don't really want to pull the thing apart again, unless I am sure that it needs to be done.
What oil level do they advice ?
You might have to much oil in the fork, that could give the same feeling as a fork that bottoms out.
The adjustment is working like a bleed adjuster.Turning clockwise would give more damping(less bleed)
Counting the turns is best from fully closed.
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Old 12-18-2012, 12:25 PM   #824
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What oil level do they advice ?
It's 430cc of SAE5, which should give an air gap of 120mm.
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Old 12-18-2012, 12:38 PM   #825
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Quote:
Originally Posted by Kokopelli View Post
It's 430cc of SAE5, which should give an air gap of 120mm.

The air chamber or oil level is used to compensate the lack of spring strength before reaching the end of the travel.
You could measure how much travel you use by putting a cable tie on the fork tube and measure the used travel.
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