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Discussion Starter · #1 ·
I bought Guide RSC brakes 2 months ago selling my previous X0 Trail.
The system was empty so I filled them and did the bleeding 3 times following exactely the procedure.
Brakes are ok and I tested several times both in enduro riding and long descends in the Alps.
The problem is:
- the lever run is very long before engaging the pads;
- pads are new and if I turn the contact point adjustment the situation is even worse.

During bleeding I turn the knob completely opposite to the arrow as per manual.

Any suggestions?
Thanks.



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Try storing the bike with the levers squeezed in. I use toe straps or zip ties to pull the levers in. It resets the pistons and seals in the calipers to make the contact point happen sooner in the lever travel. I don't notice any pad clearance issues either.
 

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I've bled my RSC's with the pistons pumped out and the dial at the half way point (50 clicks in or out). This seems to help. Initially the lever will be really good but will eventually regress most of the way back. There is some benefit doing this and you get a bit less lever throw, but its not a "fix."

I'll try storing the bike with the lever clamped too.

This seems to be the only real complain people have with the brake. Hopefully Sram will take notice and offer a fix.
 

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Try storing the bike with the levers squeezed in. I use toe straps or zip ties to pull the levers in. It resets the pistons and seals in the calipers to make the contact point happen sooner in the lever travel. I don't notice any pad clearance issues either.
Best tip ever. Simple and it works.
 

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I tried clamping the levers over night and ....... Fantastic result !! Thanks for the suggestion !
I tried this and the brake performance was a bit better. is this a long term fix? I have a feeling this will only work on the ride after you release the levers.

Also, I have never bleed a brake before so my question is if I learn how to do it can I leave more fluid in so there is more pressure in the line and restrict the levers from having so much play in them?
 

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I read somewhere to remove the wheels, pull the levers to where the pads are almost touching each other. Spread them with a pad spreader and insert the wheels and they will barely move. And repeat this step several times (I did it 3 more times) and the pads will eventually move slightly away from the rotor and stay. I had tried this several times where I just did the process 1 time and it worked for a ride or so. But when I did it several times consecutively, the pads (calipers) have stayed put for a month so far.
 

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Discussion Starter · #11 ·
I tried this and the brake performance was a bit better. is this a long term fix? I have a feeling this will only work on the ride after you release the levers.

Also, I have never bleed a brake before so my question is if I learn how to do it can I leave more fluid in so there is more pressure in the line and restrict the levers from having so much play in them?
Up to now it seems working only on the following ride. I repeat the procedure tonight and will see if it will improves.
The problem of these levers with the big oil reservoir is that when you remove the siringe after the bleeding, prior closing the hole, a lot of oil comes out.
I never had this problem with X9, X0, X0 Trail. In there levers if you pressurized oil with the siringe you could have more lever.

On the contrary with Guide it seemed to me that during long descends the perforfamce increases in terms of lever position; with elixir you could end a descend with lever quite at zero.

Let's continue exchanging feelings/experience/opinion.

Sorry for my bad english ......

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Discussion Starter · #12 ·
I've bled my RSC's with the pistons pumped out and the dial at the half way point (50 clicks in or out). This seems to help. Initially the lever will be really good but will eventually regress most of the way back. There is some benefit doing this and you get a bit less lever throw, but its not a "fix."

I'll try storing the bike with the lever clamped too.

This seems to be the only real complain people have with the brake. Hopefully Sram will take notice and offer a fix.
I confirm that storing the bike with the lever clamped, is only a temporary solution.
After a couple of ride you must clamp the lever again for at least one night.

When you said to have bled RCS's with the pistons pumped our, what does it means exactely?

Completely pumped out with no spacers?
Partially pumped out with a small spacer?

I think this could be the solution: I've read in an italian forum that you need to increase the oil quantity to put inside the system and for sure the pistons pumped out have these effect.
 

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I confirm that storing the bike with the lever clamped, is only a temporary solution.
After a couple of ride you must clamp the lever again for at least one night.

When you said to have bled RCS's with the pistons pumped our, what does it means exactely?

Completely pumped out with no spacers?
Partially pumped out with a small spacer?

I think this could be the solution: I've read in an italian forum that you need to increase the oil quantity to put inside the system and for sure the pistons pumped out have these effect.
Once you pull the pads out and squeeze the lever a few times you'll see the pistons pump out like so.

Steel Macro photography


The first time I did it i pumped it too far and the piston fell out along with all the fluid! So be careful. Also, some pistons will pump out more that others so try to even them out. I didn't use a spacer, you really don't one like you do with other brakes.

Its a bit of an experiment. See how it goes. It seemed to help with mine. And I'd suggest dialing the contract adjustment to half way (50 clicks).
 

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Discussion Starter · #14 ·
OK thanks. I will try it.
May be to avoid the pistons coming out , I could leave the pads installed and pumping until the two pads touch each other ....
 

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OK thanks. I will try it.
May be to avoid the pistons coming out , I could leave the pads installed and pumping until the two pads touch each other ....
Yes, but remove them before you bleed otherwise you risk contaminating the pads
 

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So last night I took both wheels off and pumped the brakes. Both calipers/pads barely moved at first but after pumping them a dozen time or so I was able to get them to move a good amount. Now this is where the issue happened.

Note: I am not a mechanic and know hardly anything about disc brakes. I was able to push the front pads apart so the front wheel spins fine. The rear wheel is a different story. After trying to push apart with a spacer tool, I was finally able to gain enough clearance to insert the rotor into the caliper however they are still rubbing. Hopefully I did not do any damage but going to have to bring them to my LBS.

Checked them this morning after sitting in the garage, still feel really good like they should with very little play in the lever.
 

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Discussion Starter · #18 ·
So last night I took both wheels off and pumped the brakes. Both calipers/pads barely moved at first but after pumping them a dozen time or so I was able to get them to move a good amount. Now this is where the issue happened.

Note: I am not a mechanic and know hardly anything about disc brakes. I was able to push the front pads apart so the front wheel spins fine. The rear wheel is a different story. After trying to push apart with a spacer tool, I was finally able to gain enough clearance to insert the rotor into the caliper however they are still rubbing. Hopefully I did not do any damage but going to have to bring them to my LBS.

Checked them this morning after sitting in the garage, still feel really good like they should with very little play in the lever.
If you have problems in pushing pistons back again, try to clean with isopropilic alcool all the caliper.
The o-ring arround the pistons need to be clean to properly allow movements of the pistons (this is for all brakes).

If you want to improve the movement you can buy AVID GREASE and apply it to the oring/pistons. I do it sometimes using a Q-tip and grease arround the pistons.
 

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So last night I took both wheels off and pumped the brakes. Both calipers/pads barely moved at first but after pumping them a dozen time or so I was able to get them to move a good amount. Now this is where the issue happened.

Note: I am not a mechanic and know hardly anything about disc brakes. I was able to push the front pads apart so the front wheel spins fine. The rear wheel is a different story. After trying to push apart with a spacer tool, I was finally able to gain enough clearance to insert the rotor into the caliper however they are still rubbing. Hopefully I did not do any damage but going to have to bring them to my LBS.

Checked them this morning after sitting in the garage, still feel really good like they should with very little play in the lever.
Brought the bike into my LBS last night. They were able to easily push the pads apart and the wheel/rotor fits with no issues. Took the bike off the stand and the brakes went back to the usual lever action with lots or play. Mechanic said probably air in the line but I do not want to pay another $30 or so to have them bleed...again. I might be learning how to bleed myself but this issue should not be happening time and time again.

Anyone from SRAM reading this thread and would like to provide input?
 

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Brought the bike into my LBS last night. They were able to easily push the pads apart and the wheel/rotor fits with no issues. Took the bike off the stand and the brakes went back to the usual lever action with lots or play. Mechanic said probably air in the line but I do not want to pay another $30 or so to have them bleed...again. I might be learning how to bleed myself but this issue should not be happening time and time again.

Anyone from SRAM reading this thread and would like to provide input?
you likely don't need to fully bleed your brakes. what i do in this situation is dial the contact adjust until it gives the most lever throw (this increases the volume of the master cylinder), then open the bleed port on the lever and top off the DOT fluid. what happens is as the pads wear, the pistons move out to compensate but this increases the volume in the system - so fluid needs to be added to maintain the 'like new' feel.

after adding fluid you should be able to dial your contact adjust back (opposite) and get a firmer lever feel. i repeat this many times over the life of brake pads, however when you change your pads down the line and need to reset the pistons you will need to remove some fluid from the lines which can easily be done by loosening the caliper bleed port slightly while resetting the pistons.
 
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