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Fox 40RC- seized H/L speed compression knobs

J

Monkey
Dec 7, 2003
437
0
San Luis Obispo, CA
A couple weekends ago I went to adjust my high and low speed compression on my Fox 40RC2 (I think its a 2005? Might be an '06, let me know if it matters) and the knobs worked fine. Then I went to put the protective cap back on and before the cap got tight the whole thing started spinning the base of threads, as in the piece that the cap screw onto. Since then the high and low speed compression knobs have been seized. I had them adjusted one click from all the way out before this happened. The fork has also felt stiffer and not as active. Does anyone know how to fix this?

I've rebuilt my Float before so I figure that's all the 40 needs but I'm slightly worried that I broke something. Thoughts?

Thanks in advanced!
 
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ridiculous

Turbo Monkey
Jan 18, 2005
2,909
1
MD / NoVA
I had a similar thing happen to me at the start of my season. I think your best bet is to send it in to fox to have them look at it. All of my attempts to rebuild only lasted about a day. I paid about $180 for the service and had a three day turn around excluding shipping last month.
 

fred.r

Dwangus Bogans
May 9, 2006
843
0
Your cart has unscrewed and is loose. Take the adjustment knobs off and try and tighten that rod/nut. Put the knobs back on and see if that fixes the problem.
 

ridiculous

Turbo Monkey
Jan 18, 2005
2,909
1
MD / NoVA
I rebuilt the rc2 cart per the instructions on Fox's service website. Fox was very vague in describing the issue but it amounted to it being rebuilt and luckily not replaced. I also had a bit of stanchion wear.

My fork grew very stiff and the rebound was very unresponsive even all the way out. it seemed like adjusting any of the hi/lo adjusters did nothing.
 

ender

Monkey
Mar 4, 2004
194
0
I rebuilt the rc2 cart per the instructions on Fox's service website. Fox was very vague in describing the issue but it amounted to it being rebuilt and luckily not replaced. I also had a bit of stanchion wear.

My fork grew very stiff and the rebound was very unresponsive even all the way out. it seemed like adjusting any of the hi/lo adjusters did nothing.
I see. Thanks Rid.
 

J

Monkey
Dec 7, 2003
437
0
San Luis Obispo, CA
Your cart has unscrewed and is loose. Take the adjustment knobs off and try and tighten that rod/nut. Put the knobs back on and see if that fixes the problem.
When you say tighten-- you mean turn the 15mm nut below the knobs clockwise, to tighten it around the rod (8mm) and against the lowers... right? This would pull the rod down (towards the ground if the bike is upright). BUT, since the protective cap spun that 15mm but tighter already should I loosen it now?

I'm about to dink around with it and if that fails I'm going to try and rebuild this thing. Any other advice?
 

J

Monkey
Dec 7, 2003
437
0
San Luis Obispo, CA
Hmm, so I tightened to about 50in-lb per '06 manual directions and the knobs still will not move. I'm guessing the "rod" which is the cartridge going into the fork got spun around. Could this harm it?
 

J

Monkey
Dec 7, 2003
437
0
San Luis Obispo, CA
So I took the whole thing apart and have the cartridge out of the right leg. It looks like that I twisted the 8mm rod that goes into the high/low speed compression "chamber" (or whatever the proper term is, bladder?). Does anyone have any experience with these? Do I dare take it apart? Does anyone have a write up on it?

Above I said it is an RC, but its actually an RC2.

Send it to Fox you say? No thanks, at least not yet. :happydance:

 
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J

Monkey
Dec 7, 2003
437
0
San Luis Obispo, CA
Problem solved... fyi for others,

I ended up having a Fox mechanic look at the seized hi/low speed compression adjusters. He took some channel locks and forced the knobs to move himself. He used a decent amount of force for those small knobs. I tried forcing them myself before but felt like I was going to snap something but apparently I just needed to use more torque.
 

Racebike

Monkey
Jul 28, 2008
463
4
Sweden
Good to see it fixed. However I noticed something in your submitted picture .

The Fox-tech that helped you may have spotted it, it looks like the cartridge isn't properly tightened up, the black ring around the big flat base of the cartridge is the bladder that sits inside.

Normally one would not see that at all, check the retaining nut (that presses against the flat lid) so that it's snug. It's a common problem and could cause your cartridge to leak oil out into the outers.
 

Matchew

Monkey
May 26, 2006
511
0
NH / Mass (ugh)
Problem solved... fyi for others,

I ended up having a Fox mechanic look at the seized hi/low speed compression adjusters. He took some channel locks and forced the knobs to move himself. He used a decent amount of force for those small knobs. I tried forcing them myself before but felt like I was going to snap something but apparently I just needed to use more torque.
Somewhat related,

I had the same type of problem with the preload adjuster on my 36 VAN R getting stuck. I was running no preload and the part that pushes on the spring had seized up against the top cap. I just took the cap off and used a 10mm wrench to loosen it, took a descent amount of force to free it up but it works fine now.