Sram guide ultimate rear brake spongy

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Sram guide ultimate rear brake spongy
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Posted: Jul 8, 2016 at 12:39 Quote
No matter what I do I seem to get a spongy rear brake with my sram guide ultimates rear brake, its not horrible it just never feels as solid as my front feels. I have tried all the steps and different bleed techniques I can find online, does anybody have any of the same issues? maybe this is normal maybe I am missing something? Anybody have any tricks to getting them consistent and solid? I know its possible because I love the way my front feels.

Any help would be great!

Posted: Jul 10, 2016 at 2:50 Quote
The rear brake will always feel a bit worse than the front, no matter the brake. It has to do with the extra length of hose that has a bit of flex in it. But on Guides it shouldn't be as bad as you are describing.

Have you thoroughly checked the alignment of the caliper and pads ? (I use the "hope technique" on all of my brakes, aligning the caliper without pads, and then align the pads using a small flat screwdriver, check the video on the Hope website) It does have a big impact on lever feel, especially on 4 pistons calipers. Same goes with sticky pistons.

O+
Posted: Jul 11, 2016 at 10:25 Quote
Ploutre wrote:
The rear brake will always feel a bit worse than the front, no matter the brake. It has to do with the extra length of hose that has a bit of flex in it. But on Guides it shouldn't be as bad as you are describing.

Have you thoroughly checked the alignment of the caliper and pads ? (I use the "hope technique" on all of my brakes, aligning the caliper without pads, and then align the pads using a small flat screwdriver, check the video on the Hope website) It does have a big impact on lever feel, especially on 4 pistons calipers. Same goes with sticky pistons.

Nice, I will give it a try and let everyone know how it worked for me, Thanks!

Posted: Apr 29, 2018 at 15:32 Quote
Problem: My Guide R brakes were always mushy and I could easily pull them to the handlebar. The bike still stopped, but it’s very awkward and just plain stupid that I have to pull the grips all the way to the bar. This mushy feeling was due to air in the system, not enough fluid in the system, or ‘not being pressurize’ (which will make sense if you watch this video). They’ve been like this since the brakes/bike were brand new.
Bleeding them to either this video below, or the official SRAM bleed procedure video did literally nothing at all to improve this mushy feel.

But…I think I cracked the code on how to fix this, at least for my opinion of what the brakes should feel like…and these Guide R brakes should feel as good as XT brakes!
Watch this entire video first from GMBN Tech:
https://www.youtube.com/watch?v=Xp_s-CK9CwA

This video is very detailed, does a great job of explaining all the tools/steps and it seems to match the official SRAM bleed process.
I’m referencing this video because it feels more thought out/slower paced compared to the official SRAM video. My mods apply to this or SRAM’s video, but these time stamps below reference the GMBN Tech video, not the SRAM video.

My mods apply to just BEFORE removal of the fitting from the brake lever at around the 11:42 mark.

Some notes from this video:
11:32, he closes the Bleeding Edge fitting…this is correct, you have to do this to pull air out of the lever!

11:42, he mentions “pressurize the system”, this is the catch…he’s right, the system DOES need to be pressurized...keep reading.

11:52, he mentions “pull the lever in and release”.

12:01, he mentions “pulling up on the syringe” (to pull out air bubbles), then he pushes down on the syringe to pressurize the lever again, but I do this step differently.

12:11, he mentions “push back in one time hard to pressurize the system”…but, the step below ruins this!

12:34, he has the syringe clamp closed and unscrews the fitting from the lever. THIS STEP IS THE PROBLEM!!
If the “system has to be pressurized”, removing the lever syringe fitting exposes the fluid to the atmosphere, instantly losing ALL pressure in the system!! For me, this resulted in a brake that was literally just as mushy after bleeding as before I started…what was the purpose of even bleeding them if it makes zero difference?

Here are the process mods below I made that resulted in a firm lever feel, which I could no longer pull to the handlebar, which was every bit as good as the XT brakes on my other bike.
One disclaimer first: As I have repeated these mods a few times, there is a risk: There could be TOO MUCH pressure in the system, resulting in pads that always rub on the disc because the pistons cannot retract into their bores. I mention how to fix this later…
1. For pulling air out of the lever:
a. At the 11:52 and 12:01 steps:
b. Here is my mod:
i. Make sure to pull as much vacuum as you can on the syringe AS YOU PULL THE LEVER IN AND RELEASE!
ii. Pull vacuum and hold it for several seconds…pull lever in…release lever…repeat. Do this at least 5-6 times.
c. Then push the syringe in one final time. Even though you will lose this pressure when you remove the fitting from the lever, it’s required to ensure the reservoir in the lever is full.
i. While pushing down on syringe, pull the lever in. It probably feels like you want it to, right!?
d. Remove the fitting from the lever and you’ll notice it instantly releases any pressurization you achieved, along with a fair amount of fluid getting pushed out…resulting in zero internal system pressure.
i. You probably now have a lever that is just as mushy as when you started, at least I did, not matter how well I performed the process. Keep reading.
e. Reinstall the lever plug, clean everything up.

2. Here is the mod that made ALL the difference for me:
a. Go back to the Bleeding Edge fitting at the caliper.
b. OPEN it back up, then WHILE PUSHING IN ON THE SYRINGE pretty hard, CLOSE the Bleeding Edge fitting:
i. If you imagine pressing on the syringe on a scale from 0 (not pushing) to 10 (pushing as hard as you can), push at about a 6-7.
c. This is the ONLY way you will achieve internal pressure in the system above atmospheric pressure, which is to pressurize while closing the system!

3. Put everything back to normal, install all the pads, clips, wheels, etc.

4. Remember the disclaimer above?
a. If you spin the wheel, are the pads obviously rubbing a lot?
i. Meaning the wheel spins less than 2-3 revolutions.
ii. If this is true, you have to release some pressure/fluid from the system.
b. Go back to the lever plug, curl some paper towels around the plug, but ensure you can still see the plug, and see if/when fluid comes out.
c. You need to ‘burp’ the plug…open it gradually until some fluid pushes out, it may push out quickly, so be ready!
d. Once you see several drops worth of fluid come out, quickly re-tighten the lever plug.
e. Do the pad rubbing/wheel spin test again.
f. Repeat this burping process a few more times as required.

5. For me, this process resulted in a ‘better than new’ feeling in both levers, just as good as my XT brakes.

6. There was some residual brake pad rubbing, like I had just put in new pads. This will go away after a few rides, just like it does with new pads. As the pads wear slightly, they create a clearance gap, resulting in zero rubbing.
a. When you eventually have to replace pads, I imagine you’ll have to ‘burp’ the system again so the pistons retract in their bores sufficient to install the new thicker pads.

I know that was a lot of words to describe two relatively simple mods, but I wanted to be as detailed as I could, because bleeding the Guide R brakes is a huge butt-pain relative to XT brakes, and I’ve done both brands numerous times now. And in the future, if I have to get new brakes, or build a new bike…I’ll probably just use XT from the beginning. At least with these procedure mods above, my Guide R brakes don’t completely suck until that time comes.

If you have questions, please let me know. If you have helpful tips, add them to this thread!

Or if you’re a turd and just want to talk trash, go get a girlfriend and spend less time on the internet. Or use these tips to fix your brakes and go ride. Either way you’ll be a lot less of a turd.

Posted: Apr 30, 2018 at 20:22 Quote
Fwiw I bled my guide rscs per srams video and they are firm and work great.

Posted: May 28, 2018 at 14:32 Quote
slabshaft wrote:
Problem: My Guide R brakes were always mushy and I could easily pull them to the handlebar. The bike still stopped, but it’s very awkward and just plain stupid that I have to pull the grips all the way to the bar. This mushy feeling was due to air in the system, not enough fluid in the system, or ‘not being pressurize’ (which will make sense if you watch this video). They’ve been like this since the brakes/bike were brand new.
Bleeding them to either this video below, or the official SRAM bleed procedure video did literally nothing at all to improve this mushy feel.
...

Thank you slabshaft! Your tips worked! My levers are way firmer now then they ever been.

Posted: May 28, 2018 at 17:40 Quote
slabshaft wrote:
Problem: My Guide R brakes were always mushy and I could easily pull them to the handlebar. The bike still stopped, but it’s very awkward and just plain stupid that I have to pull the grips all the way to the bar. This mushy feeling was due to air in the system, not enough fluid in the system, or ‘not being pressurize’ (which will make sense if you watch this video). They’ve been like this since the brakes/bike were brand new.
Bleeding them to either this video below, or the official SRAM bleed procedure video did literally nothing at all to improve this mushy feel.

But…I think I cracked the code on how to fix this, at least for my opinion of what the brakes should feel like…and these Guide R brakes should feel as good as XT brakes!
Watch this entire video first from GMBN Tech:
https://www.youtube.com/watch?v=Xp_s-CK9CwA

This video is very detailed, does a great job of explaining all the tools/steps and it seems to match the official SRAM bleed process.
I’m referencing this video because it feels more thought out/slower paced compared to the official SRAM video. My mods apply to this or SRAM’s video, but these time stamps below reference the GMBN Tech video, not the SRAM video.

My mods apply to just BEFORE removal of the fitting from the brake lever at around the 11:42 mark.

Some notes from this video:
11:32, he closes the Bleeding Edge fitting…this is correct, you have to do this to pull air out of the lever!

11:42, he mentions “pressurize the system”, this is the catch…he’s right, the system DOES need to be pressurized...keep reading.

11:52, he mentions “pull the lever in and release”.

12:01, he mentions “pulling up on the syringe” (to pull out air bubbles), then he pushes down on the syringe to pressurize the lever again, but I do this step differently.

12:11, he mentions “push back in one time hard to pressurize the system”…but, the step below ruins this!

12:34, he has the syringe clamp closed and unscrews the fitting from the lever. THIS STEP IS THE PROBLEM!!
If the “system has to be pressurized”, removing the lever syringe fitting exposes the fluid to the atmosphere, instantly losing ALL pressure in the system!! For me, this resulted in a brake that was literally just as mushy after bleeding as before I started…what was the purpose of even bleeding them if it makes zero difference?

Here are the process mods below I made that resulted in a firm lever feel, which I could no longer pull to the handlebar, which was every bit as good as the XT brakes on my other bike.
One disclaimer first: As I have repeated these mods a few times, there is a risk: There could be TOO MUCH pressure in the system, resulting in pads that always rub on the disc because the pistons cannot retract into their bores. I mention how to fix this later…
1. For pulling air out of the lever:
a. At the 11:52 and 12:01 steps:
b. Here is my mod:
i. Make sure to pull as much vacuum as you can on the syringe AS YOU PULL THE LEVER IN AND RELEASE!
ii. Pull vacuum and hold it for several seconds…pull lever in…release lever…repeat. Do this at least 5-6 times.
c. Then push the syringe in one final time. Even though you will lose this pressure when you remove the fitting from the lever, it’s required to ensure the reservoir in the lever is full.
i. While pushing down on syringe, pull the lever in. It probably feels like you want it to, right!?
d. Remove the fitting from the lever and you’ll notice it instantly releases any pressurization you achieved, along with a fair amount of fluid getting pushed out…resulting in zero internal system pressure.
i. You probably now have a lever that is just as mushy as when you started, at least I did, not matter how well I performed the process. Keep reading.
e. Reinstall the lever plug, clean everything up.

2. Here is the mod that made ALL the difference for me:
a. Go back to the Bleeding Edge fitting at the caliper.
b. OPEN it back up, then WHILE PUSHING IN ON THE SYRINGE pretty hard, CLOSE the Bleeding Edge fitting:
i. If you imagine pressing on the syringe on a scale from 0 (not pushing) to 10 (pushing as hard as you can), push at about a 6-7.
c. This is the ONLY way you will achieve internal pressure in the system above atmospheric pressure, which is to pressurize while closing the system!

3. Put everything back to normal, install all the pads, clips, wheels, etc.

4. Remember the disclaimer above?
a. If you spin the wheel, are the pads obviously rubbing a lot?
i. Meaning the wheel spins less than 2-3 revolutions.
ii. If this is true, you have to release some pressure/fluid from the system.
b. Go back to the lever plug, curl some paper towels around the plug, but ensure you can still see the plug, and see if/when fluid comes out.
c. You need to ‘burp’ the plug…open it gradually until some fluid pushes out, it may push out quickly, so be ready!
d. Once you see several drops worth of fluid come out, quickly re-tighten the lever plug.
e. Do the pad rubbing/wheel spin test again.
f. Repeat this burping process a few more times as required.

5. For me, this process resulted in a ‘better than new’ feeling in both levers, just as good as my XT brakes.

6. There was some residual brake pad rubbing, like I had just put in new pads. This will go away after a few rides, just like it does with new pads. As the pads wear slightly, they create a clearance gap, resulting in zero rubbing.
a. When you eventually have to replace pads, I imagine you’ll have to ‘burp’ the system again so the pistons retract in their bores sufficient to install the new thicker pads.

I know that was a lot of words to describe two relatively simple mods, but I wanted to be as detailed as I could, because bleeding the Guide R brakes is a huge butt-pain relative to XT brakes, and I’ve done both brands numerous times now. And in the future, if I have to get new brakes, or build a new bike…I’ll probably just use XT from the beginning. At least with these procedure mods above, my Guide R brakes don’t completely suck until that time comes.

If you have questions, please let me know. If you have helpful tips, add them to this thread!

Or if you’re a turd and just want to talk trash, go get a girlfriend and spend less time on the internet. Or use these tips to fix your brakes and go ride. Either way you’ll be a lot less of a turd.

This makes a lot of sense to me. Will try it out soon. Thank you so much for taking the time to type this out man!!

O+
Posted: Dec 22, 2018 at 20:41 Quote
slabshaft wrote:
Problem: My Guide R brakes were always mushy and I could easily pull them to the handlebar. The bike still stopped, but it’s very awkward and just plain stupid that I have to pull the grips all the way to the bar. This mushy feeling was due to air in the system, not enough fluid in the system, or ‘not being pressurize’ (which will make sense if you watch this video). They’ve been like this since the brakes/bike were brand new.
Bleeding them to either this video below, or the official SRAM bleed procedure video did literally nothing at all to improve this mushy feel.

But…I think I cracked the code on how to fix this, at least for my opinion of what the brakes should feel like…and these Guide R brakes should feel as good as XT brakes!
Watch this entire video first from GMBN Tech:
https://www.youtube.com/watch?v=Xp_s-CK9CwA

This video is very detailed, does a great job of explaining all the tools/steps and it seems to match the official SRAM bleed process.
I’m referencing this video because it feels more thought out/slower paced compared to the official SRAM video. My mods apply to this or SRAM’s video, but these time stamps below reference the GMBN Tech video, not the SRAM video.

My mods apply to just BEFORE removal of the fitting from the brake lever at around the 11:42 mark.

Some notes from this video:
11:32, he closes the Bleeding Edge fitting…this is correct, you have to do this to pull air out of the lever!

11:42, he mentions “pressurize the system”, this is the catch…he’s right, the system DOES need to be pressurized...keep reading.

11:52, he mentions “pull the lever in and release”.

12:01, he mentions “pulling up on the syringe” (to pull out air bubbles), then he pushes down on the syringe to pressurize the lever again, but I do this step differently.

12:11, he mentions “push back in one time hard to pressurize the system”…but, the step below ruins this!

12:34, he has the syringe clamp closed and unscrews the fitting from the lever. THIS STEP IS THE PROBLEM!!
If the “system has to be pressurized”, removing the lever syringe fitting exposes the fluid to the atmosphere, instantly losing ALL pressure in the system!! For me, this resulted in a brake that was literally just as mushy after bleeding as before I started…what was the purpose of even bleeding them if it makes zero difference?

Here are the process mods below I made that resulted in a firm lever feel, which I could no longer pull to the handlebar, which was every bit as good as the XT brakes on my other bike.
One disclaimer first: As I have repeated these mods a few times, there is a risk: There could be TOO MUCH pressure in the system, resulting in pads that always rub on the disc because the pistons cannot retract into their bores. I mention how to fix this later…
1. For pulling air out of the lever:
a. At the 11:52 and 12:01 steps:
b. Here is my mod:
i. Make sure to pull as much vacuum as you can on the syringe AS YOU PULL THE LEVER IN AND RELEASE!
ii. Pull vacuum and hold it for several seconds…pull lever in…release lever…repeat. Do this at least 5-6 times.
c. Then push the syringe in one final time. Even though you will lose this pressure when you remove the fitting from the lever, it’s required to ensure the reservoir in the lever is full.
i. While pushing down on syringe, pull the lever in. It probably feels like you want it to, right!?
d. Remove the fitting from the lever and you’ll notice it instantly releases any pressurization you achieved, along with a fair amount of fluid getting pushed out…resulting in zero internal system pressure.
i. You probably now have a lever that is just as mushy as when you started, at least I did, not matter how well I performed the process. Keep reading.
e. Reinstall the lever plug, clean everything up.

2. Here is the mod that made ALL the difference for me:
a. Go back to the Bleeding Edge fitting at the caliper.
b. OPEN it back up, then WHILE PUSHING IN ON THE SYRINGE pretty hard, CLOSE the Bleeding Edge fitting:
i. If you imagine pressing on the syringe on a scale from 0 (not pushing) to 10 (pushing as hard as you can), push at about a 6-7.
c. This is the ONLY way you will achieve internal pressure in the system above atmospheric pressure, which is to pressurize while closing the system!

3. Put everything back to normal, install all the pads, clips, wheels, etc.

4. Remember the disclaimer above?
a. If you spin the wheel, are the pads obviously rubbing a lot?
i. Meaning the wheel spins less than 2-3 revolutions.
ii. If this is true, you have to release some pressure/fluid from the system.
b. Go back to the lever plug, curl some paper towels around the plug, but ensure you can still see the plug, and see if/when fluid comes out.
c. You need to ‘burp’ the plug…open it gradually until some fluid pushes out, it may push out quickly, so be ready!
d. Once you see several drops worth of fluid come out, quickly re-tighten the lever plug.
e. Do the pad rubbing/wheel spin test again.
f. Repeat this burping process a few more times as required.

5. For me, this process resulted in a ‘better than new’ feeling in both levers, just as good as my XT brakes.

6. There was some residual brake pad rubbing, like I had just put in new pads. This will go away after a few rides, just like it does with new pads. As the pads wear slightly, they create a clearance gap, resulting in zero rubbing.
a. When you eventually have to replace pads, I imagine you’ll have to ‘burp’ the system again so the pistons retract in their bores sufficient to install the new thicker pads.

I know that was a lot of words to describe two relatively simple mods, but I wanted to be as detailed as I could, because bleeding the Guide R brakes is a huge butt-pain relative to XT brakes, and I’ve done both brands numerous times now. And in the future, if I have to get new brakes, or build a new bike…I’ll probably just use XT from the beginning. At least with these procedure mods above, my Guide R brakes don’t completely suck until that time comes.

If you have questions, please let me know. If you have helpful tips, add them to this thread!

Or if you’re a turd and just want to talk trash, go get a girlfriend and spend less time on the internet. Or use these tips to fix your brakes and go ride. Either way you’ll be a lot less of a turd.

Thank you sir!

This has allowed me to find the lever feel i'm alway searching for.... Only downside being the DOT 5.1 explosion and contamination of the rear pads... all good, can sort that.

Posted: Dec 23, 2018 at 1:33 Quote
ButtaYoBreadd wrote:
This makes a lot of sense to me. Will try it out soon. Thank you so much for taking the time to type this out man!!

Heh, look on the brightside, free and easy piston lube! lol

Posted: Jul 15, 2019 at 9:45 Quote
Makes perfect logical sense

Posted: Jul 15, 2019 at 9:46 Quote
Makes perfect sense

Posted: Oct 27, 2019 at 10:37 Quote
slabshaft wrote:
I know that was a lot of words to describe two relatively simple mods, but I wanted to be as detailed as I could, because bleeding the Guide R brakes is a huge butt-pain relative to XT brakes, and I’ve done both brands numerous times now. And in the future, if I have to get new brakes, or build a new bike…I’ll probably just use XT from the beginning. At least with these procedure mods above, my Guide R brakes don’t completely suck until that time comes.

If you have questions, please let me know. If you have helpful tips, add them to this thread!

Just wanted to post about my experience with your "mods." I bought a new Stumpjumper in June and very quickly decided that I was going to need to change out the brakes and was planning on waiting till some Black Friday sales came around. The Guide R's on my expensive, new bike left a LOT to desire.

I decided to bleed the brakes following the SRAM and GMBN videos and the brakes were even worse. I found your post and tried again this morning following your advice and oh man what a difference it has made. Its like I have a new bike! Brakes are even better than my old XT's. Glad I found your thread!

Posted: Jan 10, 2020 at 22:01 Quote
slabshaft wrote:
2. Here is the mod that made ALL the difference for me:
a. Go back to the Bleeding Edge fitting at the caliper.
b. OPEN it back up, then WHILE PUSHING IN ON THE SYRINGE pretty hard, CLOSE the Bleeding Edge fitting:
i. If you imagine pressing on the syringe on a scale from 0 (not pushing) to 10 (pushing as hard as you can), push at about a 6-7.
c. This is the ONLY way you will achieve internal pressure in the system above atmospheric pressure, which is to pressurize while closing the system!

Man this should be posted everywhere! Great job explaining everything. This is 100% the correct way to bleed these brakes. I have a set of RSCs and had to figure this out myself after a little trial and error. I came to the same conclusion that unscrewing the lever syringe, after you've pressurized the system, unwittingly releases all of that pressure. Where else would the pressure go? The caliper port is closed at that point, so it pushes out of the lever port and spills fluid all over the place! Doesn’t make any sense and whoever can get a firm lever feel, if that’s your last move, I’d love to hear how.

I also don’t agree with turning the contact adjustment all the way out, as they instruct you to turn it in the reverse direction of the arrow, thereby losing the ability to firm up the lever feel as you can only adjust inward which is a longer pull. So combine that with releasing all of the pressure and you get a horribly mushy lever feel. Not sure what they were thinking. I have been bleeding with the adjuster set halfway, which seems to be 10-11 clicks out of 21-22. Wonder what the race mechanics are doing... I’m sure they have some tricks up their sleeve.

O+
Posted: Jan 17, 2020 at 10:56 Quote
I've been meaning to do this since I got my new 2020 Liv Intrigue Advanced 1 with the G2 RSC brakes on it. They are super mushy, even with the bite point adjustment etc. I'm glad to hear that others have had the same thought that I did about "over pressurizing the system". Thank you as well for explaining what to do if you over-pressurize too much and have too much brake rub. Just a thought though, rather than open up the screw at the lever to let some out which could make a mess, couldn't you just open the bleeding edge port again while applying enough pressure to the syringe to just allow a bit of fluid to come back out? Is there a reason why this wouldn't be a good idea or wouldn't work? Thanks!

Posted: Jan 23, 2020 at 14:27 Quote
So I am a complete newbie to hydraulic disc brakes, and my new Canyon Spectral has SRAM Guide R's. They do feel very spongy. I am assuming I need to bed them in properly, and if they are still bad after that I will look at following these steps.

Honestly, it is a bit daunting to me, having never bled brakes before. Would be awesome if someone could do a video that has the proper modified steps in too, not just text descriptions!

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