Sram guide ultimate rear brake spongy

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Sram guide ultimate rear brake spongy
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Posted: Aug 21, 2020 at 20:51 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.

I have some RSC’s on one bike and never had this problem I’m guessing because of the bite adjustment. I grabbed a set of Guide R’s as an upgrade to old levels on my fat bike and I was having this exact problem. I just rebled using your mods and boom, brakes are great. This may have been the most helpful forum post I’ve read. Thanks @slabshaft

Posted: Aug 25, 2020 at 15:29 Quote
My fairly new bike (mid-June, about 10-15 rides) was upside down for about a week, and my brakes (front especially) have been pretty spongy since then. I believe the air bubbles have crept up from the lever to the calipers, causing the issue.

Do I need a "full" bleed with both syringes, or is it possible to just attach to the lever and try to pull the air bubbles out that way?

Posted: Aug 25, 2020 at 15:54 Quote
turbospartan wrote:
My fairly new bike (mid-June, about 10-15 rides) was upside down for about a week, and my brakes (front especially) have been pretty spongy since then. I believe the air bubbles have crept up from the lever to the calipers, causing the issue.

Do I need a "full" bleed with both syringes, or is it possible to just attach to the lever and try to pull the air bubbles out that way?

Yes ive seen youtube vids of pro mechanics just doing a lever bleed using the vacuum technique

Posted: Sep 24, 2020 at 7:23 Quote
I followed the suggestions in this thread (over multiple bleeds) and my lever feel and throw was still horrible on my Guide R. I could bring the lever all the way to the bar. I keep researching and found this document from SRAM:

https://www.servicearchive.sram.com/sites/default/files/techdocs/gen.0000000005811_rev_a_2017-2019_guide_rs_r_english.pdf

On page 7 is troubleshooting excessive brake lever throw. Following this procedure fixed my issues. Hopefully this helps others.

Posted: Oct 4, 2020 at 12:17 Quote
Thanks for the writeup! I went through the bleeding procedure as outlined in hundreds of youtube vids for the Guide R's with Bleeding Edge, and couldn't figure out why we were told to 'pressurize' the system from the lever side syringe, when the reservoir clearly doesn't have any sort of pressure release valve like the caliper side does. I come from the world of motorbikes and have bled every system on every bike I've had - and they universally have bleed nipples with built-in valves at the caliper, lever and reservoir. How could you ever expect to build 'positive pressure' when the fluid just leaks right out at the lever?!? Why wouldn't they put the 'Bleeding Edge' port at the lever?!? Is SRAM really this pants-on-head retarded? Have they never looked at a brake system in the automotive/motorcycle world in the past 20 years? Is their next Guide X system going to consist of supplying you with a long stick that you just jam in the spokes of the front wheel to stop?

Posted: Oct 28, 2020 at 20:53 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.

That's GOLD!
I wonder why it was not included into bleeding manuals... (I assume it's because of the high risk of brake pads contamination caused by the blown bleeding edge port)

Anyway, it worked perfectly with my Level Ultimate that felt spongy after cutting and 'standard' bleeding. The most difficult part of the entire procedure was the removal of pad spacers keeping the pads apart during this complimentary bleeding - pulling it out of the rear caliper required some 'burping' Smile

Posted: Dec 5, 2020 at 5:27 Quote
Just used this slabshaft method as well. So much better. I bled the brakes about 5x last night and the lever still felt awful on the rear. Didn't even rebleed this morning, I just very carefully filled the syringe with the bleeding edge tool, popped it into the rear caliper port, opened it up, pressurized the system and closed it back. Instantly better.

My issue was that the pads were constantly moving away from the rotor and using about 50% of lever throw to get to the disc every time and moving back out again. With no way to hold pressure in the line or system from the lever, the pads weren't even close to touching.

Posted: Jan 16, 2021 at 14:33 Quote
slabshaft wrote:
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.

Did this technique again yesterday and I'm still just amazed at how much better the brakes perform.
But I do have 1 comment and 1 question after doing this again:

1. Instead of "burping" and releasing all that precious pressure you have put into the system, I loosen the bolts holding the brake calipers to the frame. The calipers can now move side to side. I spin the wheel and then squeeze the lever to stop the spinning. While holding down the lever, I now retighten the bolts holding the calipers to the frame. The brake pads are now centered over the rotor and they should no longer rub.

2. I didn't think of this until after I finished my bleed but I am wondering if instead of applying the pressure from the levers and then closing the bleeding edge port and then sealing up the levers, could you instead apply the pressurize the system from the bleeding edge port with the lever port already sealed? That way, when you pull the bleeding edge port out, no DOT fluid leaks out.

Posted: Jan 16, 2021 at 21:09 Quote
Dangerfish wrote:
Did this technique again yesterday and I'm still just amazed at how much better the brakes perform.
But I do have 1 comment and 1 question after doing this again:

1. Instead of "burping" and releasing all that precious pressure you have put into the system, I loosen the bolts holding the brake calipers to the frame. The calipers can now move side to side. I spin the wheel and then squeeze the lever to stop the spinning. While holding down the lever, I now retighten the bolts holding the calipers to the frame. The brake pads are now centered over the rotor and they should no longer rub.

2. I didn't think of this until after I finished my bleed but I am wondering if instead of applying the pressure from the levers and then closing the bleeding edge port and then sealing up the levers, could you instead apply the pressurize the system from the bleeding edge port with the lever port already sealed? That way, when you pull the bleeding edge port out, no DOT fluid leaks out.

1. Yep, that’s how I always learned to center the brakes too.

2. Absolutely. This is what i’ve been doing as well. The initial write-up was very helpful, but this is pretty much the entire tip. Just bleed as usual or per SRAM’s instructions but just before you close the bleeding edge port, squeeze a little pressure on the syringe as you close the port.

Posted: Apr 10, 2021 at 11:57 Quote
You sir are real MVP. I thought that I will loose my mind over that issue with lever to the bar after I disconnected syringe. THANK YOU !
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.

Posted: Apr 20, 2021 at 9:13 Quote
Great stuff. Just would add that you don’t have to do this as part of a full bleed, assuming you don’t have air in the system. You can just take off the rear wheel, insert a pad spacer, hook up the Bleeding Edge tool, and pressurize it the way you described. Just did it on my wife’s Stumpy and it’s so much better. (Not quite like XT in my opinion but I would say it feels like G2.) Thanks!

Posted: May 31, 2021 at 3:12 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.

Not all hero's wear capes

Posted: Jul 24, 2021 at 11:30 Quote
Was having and technically still have it trouble with my guide r’s. Good feel and when it reaches the end of that travel I can keep going to the bars with a spongy feel even after 2 full bleeds. Did the pressurizing at the caliper like explained here. Felt great then I moved the bike and the pads locked up the wheel and fluid came out of the lever reservoir. Bled a little out to relieve it and still get the spongy to the bar problem and went back and fourth multiple times with pressurizing less/more and either too much and comes out the lever or too little and back to square one. Almost feel something is wrong in my brake line or lever?

Posted: Aug 20, 2021 at 13:33 Quote
I tried the overpressurization method and failed miserably. On first arrempt I applied moderate pressure with the syringe but it didn't improve the feel of the brakes at all. On second attempt I used more pressure which caused the hose to separate from the bleeding edge adapter and spray dot fluid all over my bike. I'm so done with SRAM brakes.

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