+ive leaking to -ive?
diy
Posts: 6,473
Is it possible that air from the +ive chamber on a set of reba forks, could leak to the -ive?
I have a problem where after about an hour of pounding, my forks suck down. I check the +ive champer and there seems to be very little if any pressure loss (but note that this is with them sucked down). The -ive also seems to be holding fine. I have used tyre leak spray to test for leaks (sort of silicon based washing up liquid) and cannot see any leeks around the air chamber. Also when I put another 20psi in the +ive, they don't return up by much, which leads me to think air is transferring to the -ive?
I'm about to give up on these forx they were not in good nick when I bought them, but I have fixed every other problem and don't really want to buy a new set of 120mm when I am looking for a new frame too.
I have a problem where after about an hour of pounding, my forks suck down. I check the +ive champer and there seems to be very little if any pressure loss (but note that this is with them sucked down). The -ive also seems to be holding fine. I have used tyre leak spray to test for leaks (sort of silicon based washing up liquid) and cannot see any leeks around the air chamber. Also when I put another 20psi in the +ive, they don't return up by much, which leads me to think air is transferring to the -ive?
I'm about to give up on these forx they were not in good nick when I bought them, but I have fixed every other problem and don't really want to buy a new set of 120mm when I am looking for a new frame too.
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Comments
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yes.
read the topic in the FAQs."Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
Parktools :?:SheldonBrown0 -
Can you point me specifically in the right direction? I can't find the article you are refering to, although I did read the SRAM FAQ which suggests I need to top up the oil in the +ive.
Failing that I thinks is going to be another strip down and seal kit.0 -
I thought I'd just update this with the fix.
My air chamber was dry, so I put 5ml of oil in the chamber as per the SRAM FAQ. This seems to have stopped the problem. However, I am not sure if the dry chamber was a symptom of the problem or the cause, so I will be keeping an eye on it.0 -
Hmm, mine did this at Llandegla the other week. Most of the travel seemed to disappear, what was left was very harsh and ramped up to being solid almost immediately. I let all the air out of both chambers and then reinflated and they went back to normal. :?
DIY: Do you mean this SRAM FAQ?0 -
Yeah, thats it. Its a 2 minute job to top the oil up and if it has worked its way down, then it just comes out the bottom when you deflate the -ive chamber anyway.
Having to do this every month suggest that the dual air system is a bit delicate. I want my old toras back from mrs diy's bike
. These rebas are a pain in the A***. 0 -
I'm guessing what happens is that the oil forms a barrier (being thicker than air) to stop the +ive chamber air being forced in to the -ive during a pounding. Gradually you squeeze the air into the -ive which sucks the fork down. Draining the -ive and resetting, will fix the problem, but only until the next time.0
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Ive had Reba's, Revelations, 2 sets of each and all dual air's which ive ridden for a good few years and never had this problem at all. Must be a problem witht the seals somewhere creating this!0
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Catch 22 - dry chamber = dry seals.0
