Oil volume RockShox Reba RL damper

Based on the serial number of my fork I believe I have a Reba RL 2010 (serial number starts with XXT10…., where other sources say the number after the the letter refers to the year, so 2010). I can however not find any service manual or oil volume charts for this model, as if it does not exist. It is a dual air with hollow lower legs.

Anyway, I serviced my fork using a 2011 manual and kits for Reba 2009-2011. Everything went smoothly until the oil volume for the motion control damper side. Manuals says 123 ml 5WT oil (for 2009 and 2011 models), so I tried this and measured the volume carefully. This turned out to be way too much, and I was hardly able to compress the fork. After removing air and the damper top cap, I could clearly see the reason for not compressing was caused by too much oil.

I removed roughly 17 ml, leaving about 8 cm of air space above the oil with fully extended legs. The damper body is about 10.5 cm, so when inserted it now goes a little into the oil. I was now able to fully compress the fork (not mounted on bike) with no air in it, but did not feel that it hit hard bottom. With the fork mounted, pressurized chambers and damper in locked position I can compress about 1 cm with a little force. Is this normal? I would like to know the exact oil volumes for this fork, so I can get as best damper performance as possible and for future service as well. It’s a bit frustrating that I cannot find the number in the SRAM manuals. Anyone have experience with this fork, or how to fine tune oil amounts?

Cheers

Hmm – interesting, I had a similar problem with 2012 reba’s & assumed I had effed up the oil volume whilst not paying attention.

I might have read that post in my preparations. Since it was the first time I did this service, I was pretty careful. I’m very certain I measured the correct volume,I used a graduated cylinder + syringe and checked it twice before pouring in. Out of curiosity that I have understood the serial number right, do you have a 12 then after the two numbers and one letter in your serial number (should be printed right below the crown)?

reksa…as you’ve highlighted, the actual volume of oil differs significantly from the service guide ones.

I too had this issue when servicing my 2012 Reba RLT’s so I called round a couple of the well known tuning companies and they both stated that it’s a trial and error process. All the oil is forced through a very small top port in the damper cartridge so if you don’t leave enough room for the oil to expand above the port then you’ll not get the full travel…too little and you won’t be able to lock out….hence the trial and error bit.

I was advised to cycle the whole damper assembly when I had the whole thing stripped down and to make sure that I got full travel & lock out before putting it all back together. As you say, the bottom of the cartridge needs to ‘just’ sit in the oil. One tech guy suggested I could play about with this level of insertion and therefore adjust the forks behaviour when being compressed but that all sounded a bit too much for my usual riding so I stuck with what I had…IWFM!

Sorry if that doesn’t provide you with an exact number but I hope it helps a little.

Thanks rosscopeco! Seems it is a fairly common issue that the oil volumes do not always match. I haven’t tried riding it properly yet, but I suspect I will stick with what I have for now if it works ok. Just curious how clear lock the damper lock-out should be, I do recall having a little movement before I did the service as well. I will contact SRAM as well to see what they say.

So I have contacted SRAM, who was very helpful.
Turns out the fork is produced late 2011, so it is a 2012 model.
The 2012 Reba RL Dual air with motion control takes 106ml in the damper, so I ended up pretty close with my adjustment. They also informed me that the locked damper should have about a centimeter of compression.

For others trying to identify their forks, my serial number started with 45T1…
45 is the week number, and the 1 means 2011 (so a 9 is 2009, 0 is 2010 etc). As for tuning the oil amount, it seems the damper should sit about 2.5-3 cm in the oil (might depend on the damper model though). I found a useful chart giving both oil volumes and distance of oil from the top here

I found a useful chart giving both oil volumes and distance of oil from the top here

Thanks for posting that, very useful.