So my 9th Reverb has developed the couple mm drop (about 5mm) when you apply pressure to the saddle – not sitting on it.

Shop has said they could send it back to Sram but could be a fortnight…and I’ll be charged for labour.

I don’t mind the labour charge as I didn’t buy the post from them and they tend to do an excellent job.

So, as said, 9th post, bought 2 and last one was bought last May and replaced in Feb this year, so this post should still be covered by the original’s warranty (2 years).

Anyway, my question – do ‘we’ know what causes the drop? And can it be fixed? Is it fixable by shop (and quicker than a fortnight) or is it a Sram only repair?

First was bought in 2011, replaced 5 times; new bike with new post and that was replaced by a longer post (second purchase), which got replaced in Feb of this year.

Each post has failed apart from the one I replaced for a longer version, but that was used for 4 weeks (whilst longer post was on back order).

Cheers.

Air gets somewhere it shouldn’t.

You can make it better but not totally fix it as I found out myself the other day. Mine was about 10mm sag at the top and it had also stopped fully dropping – squidgy last 10mm unless sitting on it.

Turn bike upside down with post extended

Operate dropper (down)

Turn bike right side up

Extend post

This worked so well for me I did it a few times but don’t think it was effective as the first go. It now drops fully and it has 2-3mm drop which is acceptable enough.

Had this problem but found that pressure had dropped, put it back up to 250psi and all was well

I sent a reverb with that problem back to Sram warranty at FIshers for a customer on Saturday . Tracking said it was delivered at 10 am today and by 12 a new post had been posted back to us . Possibly the 2weeks scenario icould be less . Not guaranteed especially over Christmas .

How are you at spanners? Check the air pressure first but chances are it’s just air where it shouldn’t be. The details of the fix vary depending on exactly which Reverb it is but it’s all broadly the same- service fixes it.

Aget it sent back to fischers, they won’t even inspect it as this problem os so common, they’ll bin it and send you a new one. No labour costs at all. I had the same problem on 5 reverbs over a two year period and each one was replaced on warranty. The last one i got back i sold it and bought a fox transfer post and have had no problems at all in 8 months of riding. Even with the great warranty and quick turn around the reveb isn’t worth the hastle.

No labour costs at all

Maybe not from sram, but the shop will charge for handling the warranty, filling forms, packing it up and posting it off etc.

If it’s a warranty job they shouldn’t be charging? Unless it was bought from elsewhere but I think you can deal direct with Fishers?

The sag is caused by some of the pressurised air (which is only used to push the post up) getting into the oil side of the piston. The oil flow in and out of the piston is controlled by a poppet valve (which in turn is controlled by the oil in remote which is a separate circuit). The oil supports your weight as it does not normally compress, but if air gets into it then it will and cause the sagging. A basic service will fix it as that involves refilling the oil, however SRAM will say that a post that is sagging should not be home serviced because the oil is now pressurised with the leaked air and can cause bits to be ejected with a bang like a cork from a bottle when you disassemble it.

I did mine and just had to cover it with a rag to contain the explosion. Since then I have avoided picking it up by the saddle and the problem is not returned. A small investment in tools and a similar job to rebuilding a shock damper. SRAM has some instructional videos.

Sorry to hijack. I need to try and fix this (myself) in one of my reverbs which is out of warranty. Am I right in thinking that the only really specialised tools needed are the two oil height things?
I’m inclined not to change any seals unless the obviously need it as the post seems fine otherwise.

If you are careful you can try the following

1. Remove post and saddle.
2. Extend post and hold in a vice carefully
3. Depressurise the air from the bottom
4. Don some safety googles and try and cover the top with a rag whilst doing the next step
5. Remove the circlip in the top
6. Remove the poppet valve with some needle nose pilers. At this point it may pop like a cork and lose some oil
7. Top up oil and use oil height tool to set corect level
8. Reassemble and bleed remote, test.
9. If post will not go down redo oil height or bleed remote.

This worked for me and lasted a few months before it started sagging again. Second time I made a mistake and cycled the post with the top cap off so the IFP moved out of position inside so had to do a complete strip down and service (IFP height tool then needed). After that has lasted 18 months so far.

me1tdown – Member

Sorry to hijack. I need to try and fix this (myself) in one of my reverbs which is out of warranty. Am I right in thinking that the only really specialised tools needed are the two oil height things?

It depends on the model. With my old one, which I think is an A2 stealth but might be an A1, all you really need is a narrow drinking straw to set the oil level. But the AFP height tool is about £4.50 so I just bought it. And a 23mm crow’s foot is useful to remove the base- it’s a pretty shallow aluminium nut so a crow’s foot gives better engagement.

OTOH I think older non-stealth ones have a bleed tool as well. Well, I bought the bleed tool thinking I needed it and it seems to be for non-stealths, anyway 😳 There’s quite a bit of variety between the models, so it’s kind of genius that they’ve managed to replicate the exact same fault in all of them…

My Reverb Stealth has just developed this 10mm drop at 11 months old, but before I send it back to where I bought it under warranty, I was wondering if other people had sent the complete post including the hose & remote or had just disconnected the ‘connectamajig’ and just sent the faulty post back?
It just seems a bit of a PITA to have to re-route the hose when it returns.

I got my bike out of the shed last week after 6 or 7 weeks and my stealth post was sagging, probably 5-10mm.
It had been stored in the down position, but after taking it out on a ride and keeping it in the house next to a radiator overnight, the post is now solid again!
Very weird! I thought it was going to be a warranty job, but will keep a close eye on it.
Has anyone else experienced this?

I’m unsure what the shop does…actually I do know, they remove the post/hose and button and send it all back to get looked at…this normally results in a whole new unit being sent up. Going back in later this week to be sent back.

I got my bike out of the shed last week after 6 or 7 weeks and my stealth post was sagging, probably 5-10mm.
It had been stored in the down position, but after taking it out on a ride and keeping it in the house next to a radiator overnight, the post is now solid again!
Very weird! I thought it was going to be a warranty job, but will keep a close eye on it.
Has anyone else experienced this?

Yes! Just done pretty much the same thing – bike’s been sitting in the shed unridden for a couple of months, brought it in the house and noticed there was a bit of squish that wasn’t there before, and after a day inside the post’s solid again…

Mine’s probably 6 months+ out of warranty though (and I haven’t had any problems with it to be fair), so am hoping it stays ok!

me1tdown – Member 
Sorry to hijack. I need to try and fix this (myself) in one of my reverbs which is out of warranty

Give it a go with a shop sending it back to Fisher and odds are they’ll still replace/fix it as if it’s under warranty. Maybe a fee to the shop to send it off, that’s it.

Fisher are just great at dealing with these (or resigned to dealing with them).

Long standing known issue also means technically your rights trump the warranty anyway.

Reminds me, got one to send off although the bushing is shot as there’s sideways play in it. That may be why it’s got the slight sag. Anyway, I might have to cough up for the bushing fix. Still probably cheaper than places that do Reverb servicing.

Some of the replies do make me chuckle when it comes to Reverbs.
Yes it can be fixed by a decent shop without sending it off.
In theory it sounds like a warranty claim, very straight forward & easily felt with, but obviously you would be without it while it’s away.
This is why we usually fix in house, especially if a customer wants a quick turn around we usually sort it the same day.