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Discussion Starter · #1 ·
Hi. I have a Rockshox Domain R (coil) that I have just recently upgraded to RC by adding the Motion Control IS damper. The damper works great but after the upgrade the fork doesn't fully extend. More specifically it stops 10mm before full travel and I have to push it in order to fully extend.

I brought it back to my LBS and he thinks that it has to do with the added oil that needs to fully circulate inside the fork and the new damper so he thinks that after a ride it will be OK and achieve full travel again.

Could this be the case? Did he possibly add more oil than recommended? Do you suspect any other reason? Please note that except for the new damper and added oil everything else is the same.

Thank you in advance.
 

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Discussion Starter · #4 ·
It doesn't achieve full travel or return to full extension??? Two different things.
Hi. My mistake. It doesn't get full extension after I press it. There are about 10mm missing and I need to lift the handlebars in order to get the full extension. Before the damper installation there was no problem at all.

Have you not gone for a ride with it yet?
Just a quick one. I will go for a proper one tomorrow and see both how it will handle after the new damper installation and also if the extension problem will be auto-fixed.
 

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Discussion Starter · #5 ·
Just returned from my ride and the problem still remains. The fork works quite well and I can feel the difference once I adjust the compression but still I don't get full extension since there are still 10mm missing.

Any thoughts;
 

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Discussion Starter · #6 ·
Since I am currently travelling abroad I couldn't take the bike back to the LBS so I am not sure about the cause of the problem but as I mentioned I suspect that it has to do with the oil levels.

Did you have any similar experience? I know that more oil can cause less travel but could it also cause less fork extension / rebound?
 

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Fat-tired Roadie
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I had an air fork that was slow to extend. Mostly I think it was worn out.
 

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This is a triple clamp dh fork correct? If so loosen the pinch bolts on the coil side and make sure its pulled up all the way.

Sent from my Nexus 7 using Tapatalk
 

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Discussion Starter · #9 ·
Hi. The fork is a single crown fork but stronger and much heavier due to steel stanchions.

Coming back to my problem and since I didn't have time to take it back to the LBS yet, I did some troubleshooting by myself considering that this is a quite simple fork.

Since the problem started after I added the motion control damper I initially removed it but the problem remained. Then I added it back and checked the spring side that we didn't do any changes and start adding some additional preload spacers and the problem was fixed!

The strange thing is that before I added the damper in the first place the fork was fully extending with only 2 spacers but now needs 4-5 to do so. Could the damper and oil cause additional frinction and therefore I need the extra preload to overcome it? Is it possible that the spring actually "wore out" or broke in and settled in its actual length after the first rides and I just noticed after the change by coincidence? Because if I remove all spacers then the non extending length further increases. Please note that I use a firm spring instead of the suggested x firm since even with the firm one I get around 26% sag.

Anyway now the fork works great but I will have it checked on Thursday by my LBS but any thoughts are really welcome.
 

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aka dan51
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Did they take the lowers off during the work? If so they may have reassembled it in a compressed state, which woud create a stronger negative spring.
Take 2 small zipties, grease them slightly, then slide them down between the wiper/seal and the stanchion. Then extend the fork fully. This will remove the added pressure in the lowers and allow full extension.
Also, the damper could have a vacuum if it was assembled in a compressed state. Unscrew it, extend the fork then screw it back in when fully extended.
If that doesnt work, then likely there is enough stiction in all the pieces to keep it from fully extending. A coil spring gets weaker as it extends, which may not be able to overcome that stiction, which explais why adding preload spacers get it to extend as you expect.
 

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Also, the damper could have a vacuum if it was assembled in a compressed state. Unscrew it, extend the fork then screw it back in when fully extended.
I second what this guy says. And just for educational sake, when you do unscrew the top cap do it slowly and and keep an eye on the lowers. Once the pressure is released you should be able to see the lowers slowly extend. Once fully extended just screw the top cap tight again. Though be sure that your bike is in a stand, so that there is no added weight on the fork that might compress the fork slightly before you screw the top cap tight.
 

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Discussion Starter · #13 ·
This weekend I will check again the fork more thoroughly to see what causes the problem.

To be honest I start to believe that it could also be spring or friction related. For example if I only use one spacer the not extending part is around 1 cm and I can feel some friction at the beginning but the more spacers I add the less it becomes and with 5 spacers it fully expends. The same thing applies also if I totally remove the damper and leave the right stanchions open. I still don't get full extension so I am starting to believe that maybe the spring just set down.

Anyway I will do some more checking and report back,
 

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Discussion Starter · #14 ·
Coming back to this thread I had a discussion with my LBS about this problem and he told me that he checked and it seems to happen also in other forks as well. Obviously this isn't really an acceptable answer but since I only had a couple of rides after the damper installation and service I decided to do some more rides and then check again.

In the meantime I have ordered another spring since the existing one seems to be too firm for me so once it arrives I could check if this is a spring related issue especially since once I remove all preload spacers but one I can see that the spring can't really hold the fork to full extention and I need to keep adding spacers untill it does. However if it isn't a spring related issue then I will service the fork again by myself just to be sure that everything should be as expected.

Anyway I don't have much complaints about the Domain but honestly I see myself buying a better fork within the next 6 months since it weights 2.9+ kg and it is not either as sensitive or as tunable as I want. Maybe the medium spring could help but i will have to wait and see. But most probably I will buy either a Pike or a Lyrik.
 

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Fat-tired Roadie
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Don't throw more money at this fork. You were probably already thinking that...
 

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Discussion Starter · #16 ·
I won't spend any more money on this except for the spring that I have already ordered. For me my current setup with the Domain RC and Kage RC is a good starting point in order to improve myself without worrying about the fork and shock and also to decide exactly where I would like to go in the future.
 

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aka dan51
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Are you certain the 10mm is gone, or are you just noticing it now? Possible that it's been like this the whole time?

Having gone through many springs on RS forks over the years, I can say they are not all the same. 3 different springs on a Lyrik will give you different travel results by a few mm each.
I've seen it with static length springs, and coil uturn springs.

If the new spring doesn't extend all the way, throw the spacers on it and ride it and be happy.
 
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