RS Recon SL Solo Air Damper assembly

hard-rider

I need to check something with my damper. After having trouble with my lockout which a seal service didn't fix I decided to have another look at the damper and stripped it to see if I could see any obvious problem inside.

I've re-assembled the damper but it will not fully slide into the top of the fork leg. It goes as far as the oil then stops because the oil can't seem to pass into the damper. It's pressing on a valve forcing it closed. The oil level is correct (120ml 5wt). The lockout is in the open position (it is spring loaded as it's a remote lockout). I've read and re-read the service manual and watched all the damper service videos I could find and in all of the the damper just slides into the leg easily.

So I'm puzzled why my damper won't go fully in. I started thinking perhaps I didn't assemble it correctly but there is nothing to it inside. On the one end there is a disc valve. I'd like someone to confirm that I have the valve correctly assembled. I've got two photos below, one showing the valve as I remember it being before disassembly (in the normally closed position) and the second photo with it unseated (which to me already just looks wrong). I'd appreciate if someone familiar with these dampers can confirm which is correct.





If the first photo is correct then I wonder if the oil volume is a mis-print in the manual and should be quite so much to allow the damper to go in.

Manual is here for reference (page 19)

supersonic

The manual file is corrupted for me - is this the Turnkey damper or Motion Control?

hard-rider

It's the basic turnkey. i.e. just locks the fork, no adjustment to damping.

supersonic

Someone had the same problem before, I can't find the post and remedy though!

Do you use the lockout a lot? It isn't the best made part of the fork, I'd be tempted to remove the whole cartridge and just cap the top of the fork.

hard-rider

I had the same problem when I first serviced the fork. I finally got it in by opening the rebound on the bottom of the leg. It doesn't make sense why it worked then because it's not related to the damper. Opening the rebound doesn't help this time.

I need the bike tomorrow so will do as you suggest and remove the cartridge. Should I leave the oil in there as is or fill it further?

Would I be able to drop a motion control damper in there instead if I need to replace the damper?

supersonic

Leave the oil the same. A moco damper should work, but would have to be a Tora 318 one. And even then I am not 100% sure, they used a different rebound assembly.

hard-rider

ok thanks.

supersonic

Oh, a possible solution:

With the rebound fully open, and the TK damper out, push the forks through their travel 10 times or so. This should bled some air out of the rebound circuit.

hard-rider

Ok will try that. I don't think that it will help much though. If you look at the first photo you'll see that there is no way for the oil to pass into the damper cartridge as the disc is completely sealing the face. On one of the YouTube videos there was a comment by someone who had a similar problem and implied that the cartridge required bleeding somehow but there was no answer to the question.

When you insert the cartridge you can hear the air being pushed through it but as soon as it hits the oil it stops dead. No amount of wriggling or twisting makes it budge.

I'm surprised that this problem hasn't come up before.

sensi10

Hi , are you sure its meant to be 120ml and not 115 ml as checking rockshox website 2010 model recon sl solo air with turnkey damper should be 115ml whats the year of your fork ?

hard-rider

It's a 2009. Interesting you say for the 2010 that the oil required is 115ml. I just looked at the 2010 manual and it too says 120ml on page 19. Are you looking at a different manual or spec sheet? I did wonder if the oil level was correct and even mentioned if there may be a misprint in the manual in my first post.

I'll look around to see if I can find any other reference to oil volumes for the fork.

hard-rider

Here is a link to an oil chart. Also specifies 120ml.

hard-rider

OK, just checked the 2010 oil chart and it indeed does specify 115ml. I wonder if my fork is a 2010 model spec even though it has a 2009 serial number (47T90051201). Am I just clutching at straws here? Perhaps I should just try 115ml and see if that works.

suspended

Hi All - just took my old (2008) RS Recon SL forks apart because the Turnkey (not Motion Control) lockout was no longer locking out (i.e. no change in compression resistance with lockout open or closed). Now I see that changing seals etc. is unlikely to help because the Turnkey damper is a unit so I'd like to open up the damper itself.

Any advice on the best way to proceed/links to diagrams would be much appreciated. Btw, before anyone directs me to the SRAM website, I already have the relevant RS manual, which doesn't show how to dismantle the Turnkey damper, only how to remove it, replace its o-rings, and refit it.

Thanks!

supersonic

Not sure dismantling will happen - the unit is a simple port orifice damper, you should be able to see a metal disc at the bottom that, as it turns, covers up the port. First thing to check is this ie is the adjuster rotating the disc?

Seals still may need changing as this stops oil leaking around them bypassing the damper.

suspended

Tx for your input supersonic - bit the bullet and dismantled the Turnkey damper myself, holding tight in case little springs went flying everywhere. Discovered a number of things: (i) as suspected, the top cap comes off the plastic body of the damper by turning it clockwise; (ii) the shaft rotates a little spring-loaded plastic disc about 5mm thick inside the damper body (took some head-scratching to get the shaft back in the right orientation - the little L-shaped slot in the shaft lines up with the port half-way up the body when it's in the closed position); (iii) the plastic disc is rotating correctly; (iv) there's a little spring-loaded metal shim bolted onto the lower, outside end of the plastic body that you have to remove to be able to see whether the internal plastic disc is rotating correctly.

About to reintroduce lowers with uppers, will keep y'all posted on success or lack thereof...

suspended

Mooost successful - following oil change all round and dismantling/reassembly of Turnkey damper (but no seals replaced), the lockout now works again. For what it's worth, I use Putoline synthetic suspension oil in SAE 5 and 15 weights, instead of RS-branded oils. As supersonic noted above, after reassembling the forks, I did need to open the damper then pump the forks 10 times or so before the lockout worked - not sure why I couldn't get it working before because it really is a simple gadget.

supersonic

Good work!

hard-rider

Sounds like your TK damper is like mine except mine has the remote lockout so there is a spring around the shaft to return it to the open position. One question. Did the TK damper just easily slide back into the top leg? Mine seems to hit the oil once it gets 3/4 down and then won't go further as the oil is unable to pass the metal disc that is seated on the bottom (with the lockout in the open position). The sram manual makes it sound so easy the way it goes in. I could never figure out how the damper is supposed to go in all the way with that disc basically sealing the damper. The hard you push the tighter that disc seals. The photo shows the metal disc that blocks the oil from passing through the slots underneath it and filling the damper when you try insert it into the upper leg. Is that how yours looked.


To get my damper in I had to part fill the upper leg then insert the damper 3/4 in and then pour the rest of the oil in above the damper then push the damper in completely. But after pumping the fork a few times to redistribute the oil the fork locks solid. I assume the oil has passed through the damper and then gets blocked by that disc so cannot pass back up thus hydraulically locking the fork. To me it makes no sense how it is supposed to work with that metal disc there.

suspended

If you also dismantled the TK damper itself, then you may have reassembled it with the shaft in the incorrect orientation relative to the internal disc. That could possibly prevent correct oilflow through the damper, which would create difficulty in inserting the damper. Alternatively, you might simply have put too much oil in the upper leg - I used 120ml (measured with a syringe) of oil. The spring-loaded metal disc on the bottom end of the damper, shown in your pic, contributes to controlling oil flow down through the damper, i.e. on rebound, not as you insert the damper into the fork. The internal plastic disc is what actually does the locking out. If you're still having trouble, open the damper and check that, when the internal plastic disc is rotated to the right (lockout position), the L-shaped slot in the upper half of the plastic shaft inside the damper is aligned with the port about halfway up the damper, then press the shaft down into the square hole in the top of the plastic disc and screw (anticlockwise) the top cap onto the damper body without disturbing all the relative orientations of the bits. Yes, needs about three hands...

hard-rider

I definitely have not over filled the oil. I too used a syringe to measure it and used 120ml. I even tried less oil to be sure it's not the oil volume without success.

My TK damper has a coil return spring inside that slides over the shaft. One end of the spring has a loop that hooks onto a small pin that protrudes through the port (the one half way up the damper) into the damper. The other end of the spring has a small hook that engages and slides up into the L shaped slot on the shaft. When inserting the shaft, one needs to line up and engage the hook on the spring with the L shaped slot, then turn the shaft 180deg once the spring's loop engages with the pin before pushing it into the square hole of the plastic disc. This preloads the spring so it has enough torque to open the damper when the poploc is released.

I'm not sure if the angular orientation of the shaft (the L shaped slot relative to the port) has anything to do with the functioning of the damper. They appear to be there for locating the spring's loop and hook and if I set it up so that the port and L shaped slot are aligned when the valve is closed then there would be no tension on the spring to return the shaft to the unlocked position.

This is such a simple device but I'm baffled as to why my doesn't work. The orientation of the plastic disc can only go in one way as there is a stop on the damper sleeve limiting the plastic disc to rotating ~100deg. There is nothing on the shaft that appears to be influential on the functioning of the lockout (as I previously stated I believe the L shaped slot is to locate the spring if a spring is used).

I'm a bit fed up with messing with this damper. I must have disassembled and assembled it a dozen times now. To remove any doubts I will try one last experiment to verify whether the orientation of the L shaped slot relative to the port has any influence. I'm going to remove the return spring and line everything up as suspended suggested in his post and reassemble to see if that works.

bykivi

Hi hard-rider,

have you solved the problem?
Bec. I have exactly the same. I tried same as you all possibilities to solve it with no success. I can't understand - so simply part... .

At this time I use my fork in "safe mode". I removed the spring and "metal disc" from the lower side of damper. But rebound must be set to minimal .

Tomorow I disassemble whole dumping leg. Maybe "rebound part" is a primary problem ...

hard-rider

Hi and welcome to the forum. No I didn't solve it yet as I'm on holiday for 2 weeks. I'll look at it again when I get back and report anything I find.

bykivi

Hi,
so I try to disassemble damper again (bec. I thought about my last opinion and rebound must be OK - I hope )

Look at the pictures ...

The Northern Monkey

Does the turnkey damper lock out?

Make sure it is unlocked when refitting, had the same issue with my Reba. If the damper was locked out, it wouldnt go far into the oil.
As soon as it was unlocked, it went in no problems.

bykivi

Hi and thank for your answer.

Yes it does and yes it was unlocked when refitting.

Now after "my damper repair" - when I press assembled fork slowly, it works fine, but when I press it fast, then lock happend (what I don't understand is why?)

supersonic

Sounds like a hydraulic lock. To be honest I'd just throw the thing and cap the top off.

suspended

bykivi wrote:

Hi,
so I try to disassemble damper again (bec. I thought about my last opinion and rebound must be OK - I hope )

Look at the pictures ...

Looking at the pics of your damper, I'd say it's in bad shape. The entire thing appears to be slightly bent and it's definitely slightly buckled just underneath the the flat below the top cap. Did you have a particularly heavy landing on the forks at some time?

bykivi

Hi,
maybe one or two times. But this problem didn't happen immediately after this situation(s). And I'm not very heavy - about 64kg with hydrapack
Hard to say whether damper is deformed or it's a defect in manufacture.
Today I'm going to check the oil volume in lower leg (hydrolock), but last time I checked it there was correct volume of oil and problem still exist.
When a damper is a problem - buy Turnkey or Motion Control? Motion Control seems to be more durable...

bykivi

Mhm,
it's possible that turnkey is deformed, so ...
http://forums.mtbr.com/shocks-suspensio ... ost7093208

camerauk

If you are thinking of replacing the turnkey unit for a motion control unit give Tf Tuned a call (01373 826800) they will sort you out with the correct unit to fit in your fork.