No forum for Wrenching? Help with SRAM HydroR piston won't come out


New Member
Feb 19, 2004
According to SRAM, I should be able to connect a syringe to the lever to force the master piston out. Not budging. Tried Air compressor.
So I'm wondering, do I need to have the brake caliper installed to the lever to make this work? Crossed my mind that no fluid is coming out of the brake hose when I try pushing the syringe. Or it's so stuck that nothing is moving.
Any Ideas ??


New Member
Jan 26, 2023
London, UK
I understand that you're having trouble getting the master piston out of the brake lever according to SRAM's instructions. It's possible that you may need to have the brake caliper installed to the lever in order to make the process work. Another possibility is that there may be an issue with the brake hose, and no fluid is coming out when you try pushing the syringe. It's also possible that the master piston is stuck and not moving.
One suggestion is to try lubricating the brake lever and the master piston with a small amount of mineral oil. This might help to loosen any dirt or debris that might be causing the piston to stick. If that doesn't work, you might try gently tapping the brake lever with a rubber mallet.
If none of these solutions work, it may be best to take your bike to a professional bike mechanic or a electric bike company, they may have the necessary tools and experience to diagnose and fix the problem.
It's always best to troubleshoot the problem before attempting any repairs, as trying to fix something without the proper knowledge and tools can cause more harm than good.