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SRAM Guide RSC brakes - caliper pistons seem stuck

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SRAM Guide RSC brakes - caliper pistons seem stuck

Old 10-03-21, 07:10 AM
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lyle.coop
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SRAM Guide RSC brakes - caliper pistons seem stuck

I have a downhill bike that's been sitting for 3 years. I bled the back brakes and that went fine. I've bled the front brakes 2x and the pistons on the calipers don't want to advance. They almost seem stuck. I've seem some video where people clean off the pistons with isopropyl alcohol and then dab the pistons with DOT 5.1 fluid. Should I give that a shot?

Before bleeding I turned the contact pad adjustment completely in the opposite direction of the arrow.

Any tips on how I should proceed?

I'm following the SRAM Guide instructional video to bleed the brakes.






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Old 10-04-21, 02:25 PM
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cxwrench
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Push them back into the bores. I use the box end of a small (9, 10, or 11mm) combination wrench. If they still seem stuck when you try to push them in lube them w/ DOT fluid and gently pull the brake lever to push them out a tiny bit then push them in. How did you manage to bleed the brakes if they were stuck out and you couldn't put the bleed block in?
ETA: And of course this shouldn't be in 'mountain biking' it should instead be posted in 'bicycle mechanics'.
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Old 10-05-21, 05:33 AM
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Originally Posted by cxwrench;
Push them back into the bores. I use the box end of a small (9, 10, or 11mm) combination wrench. If they still seem stuck when you try to push them in lube them w/ DOT fluid and gently pull the brake lever to push them out a tiny bit then push them in. How did you manage to bleed the brakes if they were stuck out and you couldn't put the bleed block in?
ETA: And of course this shouldn't be in 'mountain biking' it should instead be posted in 'bicycle mechanics'.
The pistons were are stuck inside the caliper body. So inserting the bleed block wasn't the problem. I did clean and lube the pistons with a qtip (isopropyl alchohol followed by dot fluid). They are moving a little better now. I'm going to try bleeding the system again.

Thanks for pointing out the the bicycle mechanics sub-forum.
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Old 10-05-21, 02:49 PM
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Keep lubricating them and working them in and out. Sometimes it takes a while. When you do the bleed make sure you have the block in the caliper...if they decide to let go and move all of a sudden you could very easily have a piston pop completely out of it's bore.
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Old 10-06-21, 08:24 AM
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Originally Posted by lyle.coop View Post
I

Any tips on how I should proceed?


Remove SRAM brakes,

Install Shimano Zee brakes

Done
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Old 10-07-21, 02:14 AM
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**Update.... I lubricated the pistons and finally got them all moving. I bled the system again and it feels good.

Only problem is lever reach is way too far. I turned the lever adjust knob counterclockwise all the way and it doesn't seem to move the lever at all. Turning it clockwise doesn't move the lever either. I wonder if the knob disengaged from the adjustment mechanism.



Last edited by lyle.coop; 10-07-21 at 02:18 AM.
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