Help! RS Reba SL losing travel!
I recently had my fork rebuilt. I had them increase the travel from 95mm to 115mm (they removed the spacers). All was well for several rides and then last time out, I noticed that the front end of my bike seemed a bit low. I checked both chambers. I have the neg set at 110PSI and the pos set at 120PSI (I weigh 170). The pressures were fine.
Went for another ride again today and the front seems even lower. As though it's an 80mm travel fork. The fork bottoms out if I am not careful. Checked the pressures in both chambers again, both right where I set them.
What's going on here? I am looking for some input before I take it back to the shop where I had the work done.
Completely release the air from both chambers. Fill the positive first then the negative - do you now have full travel ? If so pressure is bleeding between the chambers. You mentioned a rebuild but the o-rings may not have been replaced or damaged .
Results: When I released all of the air out of the bottom chamber, the fork immediately extended to full travel by itself.
I then released all of the air out of the top chamber (no further change in travel) and refilled it to 120PSI. Then I refilled the lower chamber to 110PSI. The travel dropped about 3-4mm. I cycled the fork several times and the travel dropped another 5mm. I cycled it many more times and the travel remained the same. I checked the lower chamber pressure and it had dropped to 100PSI.
Does this prove your theory?
I never really monitored my pressures when I had travel loss. Positive pressure would have to enter the negative to cause the loss. I replaced the air spring o-rings (plenty of oil / grease) and the problem was remedied. This did happen on two Dual Air fork's I have owned.
Keen's right, normally when this happens it's a case of air bleeding from the POS into the NEG chamber. To fix it sometimes it's just an easy case of opening it up, cleaning and properly lubing the o-rings and reassembling, sometimes you actually need to replace them.
I'd still call the shop and let them know what's going on so they have an early heads up that somethings not 100% with the service they provided and if you happen to get it somewhat sorted and it lasts for a week or two, but then happens again and you take it back they're not going to say it's your fault.
FYI, RS forks are the easiest to fix and service, something if you've got the least bit of mechanical aptitude you should be able to do yourself. RS has the PDFs on their site and I'm sure there's a video or two on YouTube showing how by now.
UPDATE: I took the fork into one of my local shops, where it was rebuilt in August. Turns out that some dirt got inside the fork some how and that dirt had folded something over inside (o-ring?) which allowed air from one chamber to leak into another.
Anyway, all fixed, no charge and they got it back to me the very next day! Now, that's service! I've ridden it a few times now with no further issues!!!
Alternative factsman, at your service!