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Hi all. Long time lurker first time poster. I have a set of SRAM Code Rs that have done me well for years. Until now.

Recently I had a crash, talking with my shop we determined the front lever master cylinder was shot. I bought a new RSC lever, cuz why not.

Installed new lever, did a thorough bleed, dropped the pads and wheel back in and now I've got something funny going on with my pistons. It seems one is sticky - reluctant to fully extended, and the other 3 are the opposite - extended out too far and don't fully retract. I did the qtip/floss hack to clean them, to no avail. I also "worked out" each piston by squeezing the lever with the pads out and holding back the other 3 pistons.

Basically - TLDR - 3 of my pistons extend too far and don't retract, and 1 doesn't extend fully. What's my best course of action? I see that sram sells piston rebuild kits. Install new pistons? New caliper? I'm going to talk with my shop as well, but just wondered if anyone has run into this issue before and was able to remedy it.

Thanks all.
 

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Basically - TLDR - 3 of my pistons extend too far and don't retract, and 1 doesn't extend fully. What's my best course of action? I see that sram sells piston rebuild kits. Install new pistons? New caliper? I'm going to talk with my shop as well, but just wondered if anyone has run into this issue before and was able to remedy it.
Yeah... what you're dealing with is four separate pistons, and it's impossible that the friction will be the same on all of them. We hope that they'll be close enough that they'll operate without issues, but they'll never be exactly the same. Sometimes you get what you're seeing right now.

Over time, the seals harden and scrunge accumulates on the surfaces, resulting in unequal extension and retraction. The simplest solution is to push the pistons all the way out. Clean out the bore the the seals with your alcohol drenched q-tip. Clean the pistons with a Scotchbrite or steel wool and alcohol. Be gentle with everything. Apply a film of brake fluid before reassembling.

Another solution is to clean similarly and lube with disc brake assembly lube. See attached image. I think SRAM makes their own product. Don't confuse this with brake caliber grease, which is what you DON'T want. Use the lube sparingly. The risk is that everything will work TOO WELL, and the pistons will extend a little further than you want, resulting in close clearances between the pads and rotor.

Lastly, install new seals.

Bottle Liquid Fluid Bottle cap Plastic bottle
 

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Ive had similar experience with SRAM Code RSC and did the same holding 3 pistons cycling one piston clean it etc....

In the end I pushed fluid back and forth several times and kept knocking the caliper eventually a couple bubbles came out and it was much better. I still did get one caliper side that seems to push more over time.

In the end I ditched the SRAM brakes
 
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