Brake bleeding success story

Just wanted to share a positive experience bleeding my SRAM Red HRD brakes over the weekend. I was giving the bike a clean after a dusty ride and had the rear wheel off without a pad spacer in and pulled the lever a few times to check the alignment… pulled too hard and popped the piston out. Disaster!

Already had a SRAM bleed kit and decided to go balls deep and give it a go after watching the SRAM/Park Tool/GCN videos.

After accidentally pushing air into the system, I restarted the process from scratch and successfully bled the brakes. Would highly recommend giving it a go if you have a kit and the tools and patience. Interested to hear other TR users’ experiences!

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Good to hear, have a frame due to arrive in December and will be installing a Force axs group. First time putting together a frameset.

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One of my sram force hydraulic brakes has too much travel on one of the levers. I’m thinking doing another bleed or if there’s some other trick I don’t know about? I’ve bled brakes before but still feel like I’m missing a trick somewhere when taking the bleed syringe out.

I had a similar issue, turns out I neglected to pressurise the system before I finished the bleed, which led to excessive throw.

The Park Tool guide is very easy to follow, a little more detailed than the SRAM guide.

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Thanks man! I went through everything and found the pistons were sticky from this past weekend cross race that was sandy and muddy. Always good to get any advice and techniques on hydraulic brake Maintenance.

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I used a bit thinner bleed block diy-ed from chopped credit cards. Standard is 10mm, I’m using 8mm in order to overfill the system a bit. It gives me better break point. Do not over do it!

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Yeah I’ve had issues with sticky pistons as well on - fixed it after I gave them a clean in DOT fluid.

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I just had a sticky piston issue on my MTB as well. Same solution.

As far as bleeding goes I built up a new CX bike over the summer and decided to do the whole build on my own for the first time. Brake bleed on SRAM Rival AXS was honestly pretty easy. Have since done it on 3 more bikes and once you get the hang of it it’s pretty easy and gives you the ability to really dial in the feel of your brakes.

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+1 to slightly overfilling. The first time I bled the SRAM level brakes on my MTB I was having trouble pressurizing the system which made my levers feel a bit spongy. I was fairly confident that I got all the large air bubbles out, so I ended up using a hex key that was slightly narrower than the bleed block to overfill a bit and it worked quite well - though, something plastic would probably be safer to ensure you don’t damage your pistons.

Another option that I’ve seen recommended is to pressurize the system from the caliper end rather than the lever end (assuming you have a bleeding edge port). I think I’ll try this next time since overfilling is a bit finicky to get right.

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Yeah it’s definitely worth trying if you haven’t done so before, as long as you have the tools required. Biggest pain in the arse for me was holding both of the syringes up whilst pushing/drawing air out of the system, I can see why the park took bleed kit has syringes that mount to the frame.

I feel like the biggest issue people (well, me at least) had was the awkwardness of using the syringe and getting it on/off without contaminating the system with air. I’ve simply been doing gravity bleeds on all my bikes now and never have any issues, brakes feel great, not as awkward and as a plus it’s a lot cleaner.

On sram systems with dot 4 brake fluid? Good to know if so, I’ve had nothing but nightmares with these in the past.

I definitely wouldn’t be doing this on SRAM brakes given they require DOT fluid and need to be pressurised properly; might be fine for brakes that use mineral oil?

I had issues with excessive lever travel on force axs. bled them several times and the problem persisted. the problem was so bad that I couldn’t put the levers on the right reach adjustment because they would reach the bars when braking.

I found out that it was because of the pistons not going out freely enough and not resetting. They were always going away too far back into the calipers. I removed the pads and cleaned the pistons, added some dot fluid to get them going and had them go in and out a few times. It was night and day.

Hope this helps.

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