SRAM Guide RS stuck lever

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SRAM Guide RS stuck lever
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Posted: Jun 7, 2016 at 4:57 Quote
The major problem of the Guide RS is the lever assembly. When it's left out in the sun the plunger swells & the spring isn't strong enough to push it back to the open position. The distributor in my country chosen fix is to sand the plunger above the o-ring so it clears the bore. The rings & spring side are not touched so you don't leak brake fluid.

You can tell that you have the problem if your lever is slow to return & to bring it back to normal you cool the lever assembly with a cold pack or ice.

If only they used better material for the plunger & that new Bleeding Edge port for the caliper & lever then it wouldn't be such a headache.

The section highlighted in red had swelled up & was sanded by hand, as even as we could by hand, & the problem seems to be gone.


We made sure to use DOT Compatible Grease when we reassembled everything from the calipers to levers.


Posted: Jul 15, 2016 at 22:18 Quote
Has anyone tried just lubricating with the dot compatible grease?

Seems like it would be worth it, to scale from least to most extreme procedures.

Posted: Jul 15, 2016 at 22:52 Quote
Yup, I have twice before I had to sand it. It's a big problem in my country where the average temps are in the high 30°c.

No reviews mention this problem I'm guessing because they don't have ambient temps like us.

Posted: Jul 16, 2016 at 9:38 Quote
Yes, I also was very pleased with the brakes until higher temperatures in June.

Do you have an estimate of how much material you took off?

Posted: Jul 16, 2016 at 11:05 Quote
No, it was trial & error. I did use 1000 grit paper to take off material slowly. You will see galling spots & be tempted to just work on those areas but I think it best to go evenly.

Posted: Jul 16, 2016 at 15:32 Quote
Looks like the RSCs have a different assembly that threads into the body of the lever. I wonder if they avoid this issue? I'm guessing that since the RS hold it with a snap ring that the parts are not interchangeable across models, can anyone confirm?

Posted: Jul 16, 2016 at 22:38 Quote
Yup. The part is different, that's for Contact Pad adjustment. I bet they don't have the problem.

Posted: Jul 31, 2016 at 11:00 Quote
Lever is returning slowly again & pads are dragging. Opened it up & found the center of the plunger had signs of galling, sanded them carefully so I don't destroy the o-rings. The plunger can now move freely in the bore with a little lubrication. I'm guessing the RSC will probably develop this problem too.

The raised portion in green highlight & not the o-rings


Posted: Jul 31, 2016 at 11:39 Quote
Just sanded the red portion from the original post, left the brakes in the sun. It is definitely better than before, in that it doesn't get stuck down. The action is still a little sluggish. I'll take it though, it was bad enough that it was causing significant drag.

It's pretty easy to pull the plunger out, though you have to get the snap ring perfectly aligned to have clearance for the snap ring pliers.

Didn't notice any issues yet at the green area you highlighted.

Posted: Jul 31, 2016 at 12:11 Quote
Good to hear you got yours fixed. I had to force the plunger out every time I take it apart & this time the top part was clean & the two "green" sections had marks.

Have you tried servicing the pistons in the caliper? I had a huge jump in power after I got to clean & lubricated with DOT compatible grease. Getting all the pistons working perfectly also made the lever feel extra firm.

Posted: Aug 15, 2016 at 10:33 Quote
I have this Issue now, Glad I found this!
I contacted my dealer as the brakes are only 5 month old and I'm curious to see what they come back with.

Posted: Aug 19, 2016 at 15:04 Quote
festusjrf wrote:
I have this Issue now, Glad I found this!
I contacted my dealer as the brakes are only 5 month old and I'm curious to see what they come back with.

AFAIK Sram has a 3 month backlog on swapping out these levers because of this issue, I know I have the same issue and have been thinking of just replacing them with Saints...but seeing as the RSC has a different assembly, it might be worth it to get those.

Posted: Aug 20, 2016 at 1:27 Quote
asboites wrote:
festusjrf wrote:
I have this Issue now, Glad I found this!
I contacted my dealer as the brakes are only 5 month old and I'm curious to see what they come back with.

AFAIK Sram has a 3 month backlog on swapping out these levers because of this issue, I know I have the same issue and have been thinking of just replacing them with Saints...but seeing as the RSC has a different assembly, it might be worth it to get those.
On another forum the RSC do get this problem as well.

Posted: Aug 24, 2016 at 21:20 Quote
About a year ago I bought a new $5k Specialized Enduro (with SRAM Guide R's). I had to take it into the bike shop today to figure out this rear brake-sticking problem. Locks up completely, especially on hot days. The first shop guy blamed it on maintenance, saying I need to bleed them. I told him the bike is relatively new with few rides. After several minutes of bickering with him, the guy finally broke down and said I could speak to their mechanic. The mechanic KNEW ALL ABOUT this issue with Guide R's and RS's. He said "but you won't find a tech sheet or anything public about this from SRAM" because they don't want to highlight the issue. Further, the mechanic offered to make the repairs for no charge, whereas the first ship guy would have had me running in circles and charging me for it. So with SRAM sticking their head in the sand to avoid addressing the repair costs for their factory defect, I'm hoping to help spread the word about this factory defect, and that if you PERSISTENTLY PUSH them, you can probably get this common issue with SRAM Guide R's and RS's fixed at no cost. I don't have the bike back yet, but I'm optimistic.

Posted: Aug 25, 2016 at 1:07 Quote
The problem I believe is the plunger/piston material. There has got to be a better material than the plastic they are currently using.

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