I’m into week three of trying to get a set of brand new Reba RL 120 29er solo air forks set up.

For my weight the guide on the fork is telling me I should put around 105 to 120psi in them.

To get 20 % sag I’m having to go down to about 45 psi.

To ‘magic carpet’ a rocky descent, and get a degree of small bump compliance, I’m having to go lower than that, but then the sag is over half way in the travel.

On my initial outings I thought I’d cracked it with 50 psi and by winding the rebound further towards fast, but on the next ride it was banging me all over the place rather than calming the trail for me.

I know it takes time to get a fork the way you want it but this one seems to be taking the piss!

Ignore the pressure guide. Just put what ever pressure is required to get the correct amount of sag.

If its still harsh with 30% sag check if you have any volume reducers already installed and try taking them out.

And check the low speed compression dial is set to fully open position.

Given RS’ usual level of quality control, when in doubt, strip them down and make sure everything has the correct oil levels and is properly lubed up.

As above, ignore the pressure guide.

If they are new then they should bed in after a few rides and feel less harsh.

Sounds like the classic -ve spring not pressurising/over-pressurising issue.

You probably need to clean the little bleed port between the +ve and -ve air spring which means a strip, clean and reassembly. The red grease they use in the factory is so thick it blocks the little hole and the forks feel as you have described.

GB

Are you able to achieve full travel with all the air removed?

I know the air charts aren’t accurate but ime they’re not that far out, recommended 105 vs actual 45, eh? Sorry but that just doesn’t sound right.

Send them back, not worth messing with when they’re under warranty.

Might be high air pressure in the lower legs, very common problem on solo air forks and I also get it on my dual air rebas, can be sorted by letting it out the bolt holes or by carefully putting a zip tie in the seal like this (don’t bother with letting the air out and squishing right down etc)

various threads online eg http://forums.mtbr.com/shocks-suspension/air-pike-lowers-psa-929695.html

[video]https://www.youtube.com/watch?v=blHaC1mMiWM[/video]

Hmmm, i’ve had issues with mine:

http://singletrackworld.com/forum/topic/help-what-have-i-done-to-my-rochshox-reba

http://singletrackworld.com/forum/topic/rock-shox-solo-air-troubleshootingservice-gurus

I bet their harsh due to air in -, try the bleed valve as a first port of call (Solo Air side, remove bottom bolt, peek inside & there sits a valve to depress).

Thank you, one and all

but what he said………..did it

BIGJIM….very grateful…I had never heard of this….I burped it, and the bike flew through rocks and bumps like it bloody well should have done in the first place. It was a pleasure to ride, instead of a liability. And so it should have been…the fork is on a Pivot Les frame, and I was on a real downer over the issue.

QWERTY…..that’s interesting…thanks for posting

Good stuff. Given it has happened on 3 out of 5 rockshox air forks I’ve had there must be a load of people riding around with slightly crap feeling forks.

Mine just went back under warranty yesterday. Exactly the same symptoms as above (2013 solo air Rebas). Never felt right since I bought them. They’ve already been back and had the lowers / busings replaced once. Burping air using the zip tie trick works sometimes but they still feel like crap compared to my old dual shock Rebas. Limited to choice now though for 1 1/8″ steerer 26″ forks.

After that blinder of a ride that immediately followed ‘burping’ the forks as per Bigjim’s suggestion, my Reba has reverted to not feeling right in any setting. I came off Black Combe on Wednesday with the thing fighting me rather than helping, and after stopping and adjusting several times I ended up with the rebound all the way to slow, and the air pressure back down to 50 psi to get anything like a reasonable feel to it.

I discussed it with the Sram Tech guys yesterday and they reckon it is best sent back on warranty. They say Qwerty’s and Bigjim’s suggestions will only work in the short term as there is most probably an air leak somewhere. They didn’t commit themselves beyond that. I did ask if I could service it or take any other steps myself to rectify the problem, and they said no, best not to. I know two fellas who have been happily using the same model fork, so maybe there is some specific occasional component failure!

Heh Ho…….

How, who, we’re you communicating with the SRAM Tech guys? And contact details please.

I just rang the number for the SRAM Tech Centre given in the Fisher’s catalogue. I am in the trade…not sure if that makes a difference! I’m afraid I didn’t get the name of the fella I spoke to, but I outlined the problems I had had and he reckoned it was an air leak and that I wouldn’t be able to fix it myself. He didn’t say, but I got the impression there must be some faulty component that needs swapping out. My forks were brand new from Fisher in the last two months and have only been on the bike for about three weeks, that’s why I rang them, rather than TF Tuned. If the fork wasn’t a warranty issue I would probably have gone to TF Tuned because they have a reputation for saying it as it is….if you know what I mean.

I’m going to package mine today, get a returns number (I think that you have to be Trade to do that…not sure) and post them off to SRAM and see what happens. The fella reckoned they were on a 4 day turn around.

They are not right though!

Qwerty…..Re SRAM Tech Centre…… If you are non- trade they are saying contact them by email at info@sramtechcentre.co.uk. They promise to get back to you within 24 hrs.

The ‘burping’ thing is bonkers. All it does is release air (thats leaking from a faulty air ashaft seal) from the lower leg. In other words if you need to ‘Burp’ your lowers you clearly need to remove and replace one (or all 3) of your air o-rings on the air shaft.
Repeatedly burping your fork is a bit like pumping up your tyre that has a slow puncture rather than fixing the puncture.
I’m not saying I’m a know-it all but speak to any service centre such as Mojo or TF or whatever and they’ll agree. This burping thing seems to be a forum generated myth thats spread like wildfire

It did work in the short term tho so I’m grateful to Bigjim for telling me about it.

I think it must be more than a seals or O ring problem if they are telling me to send it back, because I could have done that and saved them work. But we’ll see.

This burping thing seems to be a forum generated myth thats spread like wildfire

It’s not a myth because it actually works; pressure builds up in fork lowers affecting their performance, some manufacturers fit bleed valves to some forks to get round it.

It still seemed to happen on the Revs I had even after a full seal replacement though from memory there were a few weeks without problem. It isn’t too surprising it happens when there is only little o-rings and a little lubricant to provide a seal between a lot of psi and atmospheric pressure in a structure that moves a lot.

The bleed ports that feature on some forks (Fox 40 for example) are there purely to overcome natural atmospheric pressure that can equate to small pressure build up when you reach the top of a 3000ft mountain. The only reason your fork lowers will repeatedly get a build up of pressure at regular low altitude riding is from an air leak from the air assembly.
If your fork repeatedly gains pressure in the lower leg its due to an internal air seal that is failing.

Bigjim its normal for Sram to request they do the warranty repair as they have no idea how good or bad a customers skills are. Plus they will often replace the air shaft assembly if they find any small marks on the shaft.

I spoke to TF Tuned about this the other week and they confirmed that burping is nonsense.
It is not a normal characteristic for lowers to become charged with air and that its the result of a dodgy air seal on the air assembly.

If your fork repeatedly gains pressure in the lower leg its due to an internal air seal that is failing

Yes exactly, but it isn’t a myth, it happens to me and many others. Letting the air out the lowers via the seals or bolt holes is a fix to make your forks perform as they should, the solution is something that stops it from happening in the first place. Sending them off to fishers is great if you are still under warranty but on an older fork that stills suffers after seal replacement, letting the air out is a good working fix.

Q. Have you ever worked in a ‘Research And Development’ job for a company called RockShox?

A. No, never knowingly!

Q. Well you have now! Was the pay any good?

A. No. In fact…… it cost ME a lot of money!

It happened to me with a set of brand new Sids. I read somewhere that you let all the air out, then pump it up in increments, cycling the fork each time to equalize +vet and -ve springs. I can’t remember but say… 30psi at a time? Either way, it worked and the forks are lovely and supple.

It seems I’m getting a new fork on a straight warranty replacement basis. I have just asked what was wrong with the old one via email. I’ll post if I get a response or if some kind of explanation accompanies the new fork when it arrives.

Cool. Be interesting to hear what they say. I’m still awaiting a reply to my email.

Sorry folks…my father has been quite seriously ill so I haven’t gotten onto Sram Tech. I did have a look at the message I sent and they have avoided answering my question about what was wrong with the old fork. They simply reiterated that a new fork was on it’s way.

The fork has arrived and I fitted it yesterday. It is configured slightly differently. The recessed bit you feed the axle into is more lipped, making the task of getting the wheel in and out more difficult, and the rebound adjuster is way easier to turn. I’ve only done about 15 miles on it and I can’t say I’m instantly at ease with it…but early days… it does feel better than the last one though.

I tried the cable tie trick on my Rebas this morning before a reasonable ride in the Yorkshire Dales and it made a fair size difference to what it felt like before. If you’re riding your bike a lot you’ll notice the decrease in performance significantly. If all you do is dispute things on a forum rather than ride your **** bike then no, you won’t notice a difference.

In the ridiculous number of hours I’ve ridden various forks, one thing is clear, MTB forks need a good deal of maintenance and care to keep them working as intended.

Billyboy – If it’s this years Reba that sounds about right. The harshness will start to ramp up after about 200 miles. This would be down to the burping thing and a lack of oil in the lowers, which is typical of Rockshox at the mo. (On good authority from a mechanic who deals with a lot of builds, although he still uses Rock Shox forks!)

A lot of forum posts I’ve been reading lately seem to point at the fact that SRAM are shipping forks without adequate oil in the lowers, or with too much grease which blocks the air transfer port between the pos and neg chambers.

Add that to the fact that these forks are made in the far east, spend a few months sat in a shipping container in all kinds of temperatures and humidity, then may have spend a further year sat in a warehouse somewhere, and who knows what state the oil is by the time it gets taken out on the trails.

A few of the posts on MTBR recommended that all new forks receive a full stripdown, new oil and grease before riding for the first time. Now I know that places like LoCo and TF Tuned do this for you if you buy a fork / shock from them, so it does make sense.

I still haven’t had time to fit the new Reba SRAM sent me last week as a replacement for my dodgy one and I’m tempted to do a full stripdown and service before I do fit it. Its getting harder and harder to find straight steerer, 15mm axle 26″ forks in 120mm and I was hoping to get at least a couple more years out of my frame before having to buy a new bike.

TF Tuned have an interesting bit on their FAQs Rockshox section about Solo Air. They seem to be suggesting………converting to a coil spring is the answer. When I get a chance I’ll give them a ring.

Devash: I have a set of straight steerer floats I’m looking to move on if your interested?
2013 RL’s in white, 180 steerer, 15mm axle, 140mm but can be reduced to 120. Not been used for a year after being serviced as I was injured then went 29.
Drop me a line on my profile address and I can send some pics over if your interested ?

@stayhigh Thanks mate but the steerer will be too short for my frame. I need at least 200mm.

TF Tuned say you cannot convert these newer Reba forks to a coil spring.

They suggested putting a bottomless token under the air top cap, so you can run it at lower pressures to facilitate small bump compliance, while preventing the fork diving straight through it’s travel at the first big hit.

The warranty reba fork they sent me has just gone back. It was the same as the first one. There was no small impact, nor any other size of impact, compliance unless I ran the thing way down near 45psi. It had the same build up of air pressure in the air side outer. The first time I burped it, there was a meaningful improvement in suspension performance for the ride immediately thereafter, but from then on it reverted to piss-poor.

I had a long conversation with SramTech.

They say they do not have any common problem with these forks.

I still do not know what was wrong with the first fork I sent back but they say a new replacement fork is commonly sent out if they do not have the part in stock which they’d need to repair your original fork. And I still do not know what that part might have been.

So I’m none the wiser, other than the two brand new Reba 120 29er RL forks I have had were awful to ride. And the cost of the postage back is starting to mount up! They do not collect anymore.

I’m currently back riding a bike with a Fox CTD 100 29er 2013 fork, which I seem to remember was not well rated by the mtb press, and that is way superior to both those Rebas I had.

Exactly the same the fox ctd’s are back on my bike. The reba’s are packed up and are going to tft to see if they can do a spring conversion.

They say they do not have any common problem with these forks.

Well given the attitude of their service centres like TF Tuned in the quote below from earlier in this thread, it would seem they’ll never find out about the problem either. There’s plenty of people on here who have had this problem as well as the mtbr threads etc. Must be loads of people who don’t realise they have it too. I wonder if there was a bad batch of o-rings, or if the design is flawed and a double seal is needed, or what. Anyway I use an MRP Stage now so no such bother!

I spoke to TF Tuned about this the other week and they confirmed that burping is nonsense.
It is not a normal characteristic for lowers to become charged with air and that its the result of a dodgy air seal on the air assembly.

Yet another chat with Sram Tech yesterday after they received my fork. They have warrantied this second fork I sent back because it was creaking!!!! The outer assembly was suspect, nothing to do with the problems I am beset with! They still couldn’t tell me why the first fork was exchanged on warranty.

I discussed my problems. The man reckons, as do I, that it is an imbalance of the negative and positive air. I think they have manufactured a duff batch, because my mate has been riding the same fork but an OE one, and that has been ok. I’ve ridden it, it was ok. Sramman didn’t seem to like that idea.

He reckons that when you get this problem, you should totally deflate the fork, then pump it slowly back up, and then slowly depress the fork into its travel and you should hear a hiss. That hiss will be the negative air chamber equalising with the positive. So if you have a Reba, you will also have to permanently carry a shock pump with you!! He seriously suggested the recommended pressures were good. I think most folk will say different. And he says he’s going to send out some bottomless tokens for me to try with low pressures in the new new fork they are sending to see if that works for me.

He made it very clear that there would be no refund, even if this third fork was faulty.

You never know…except I kinda do know.

Anyone want to buy a brand new boxed up reba fork at cost price?

He reckons that when you get this problem, you should totally deflate the fork, then pump it slowly back up, and then slowly depress the fork into its travel and you should hear a hiss. That hiss will be the negative air chamber equalising with the positive.

I’ve actually tried this with some success recently, but the harshness comes back eventually, say, after a couple of rides. I’ve heard success stories from some people who sent their forks to TF Tuned, Loco, Mojo etc for a full strip and service, as apparently SRAM / Fishers had used way too much grease which was causing the pos / neg air chamber valve to block.

I can’t see myself buying another RS fork though until they either move back to the good old dual air system or refine the solo air system. A combined total of 10 weeks without a ridable bike and postage costs back to Merlin has negated any savings I made by buying online.

Predictably the latest fork sent out seems to be exactly the same. I did a twenty miler for its first ride, and it started out feeling like a normal suspension fork. By the time I got to the bumpier mid section of my ride I was starting to have doubts. By the time I got to the end it was situation normal…bloody useless and knocking me about rather than absorbing the bumps for me. I did the ‘let the air out, pump up, then depress routine’ and there was no difference. I then tried 3 bottomless tokens before riding home, but it didn’t seem to make any difference, so I put a fourth one in before setting off. If anything they seem to make things worse when you run the fork at low pressures. I’m going to try with 2 later today but I’m not hopeful!