Sram Rival Hydro lever pull

joey54321
joey54321 Posts: 1,297
edited March 2019 in Workshop
I am still getting to grips with hydraulic disc brakes, when they work then great but as soon as there is a problem I am at a complete loss.

At the moment I am finding lots of lever pull in the front brake. The lever feels smooth, but just takes a long time before the pads make contact. It feels like if it were a rim brake bike that the pads were just set far away from the rim, however with hydro discs they are auto adjusting for pad wear, right? I don't think there is any air in the system (though there might be) and I bled the brakes not that long ago (~3 months).

Any advice? What it might be?

Comments

  • whyamihere
    whyamihere Posts: 7,702
    How does the lever feel once the pads have made contact? Is it firm or spongy? Does the shift lever come close to touching the bar? How much depth is left on the pads, and is the rotor above the minimum thickness?

    If the pads and rotor are good, it's got a firm feeling and the shift lever isn't coming close to the bar, then it's fine. Sram HRD brakes do have a longish lever feel, particularly if you set your cable brakes up to have little free stroke.
  • joey54321
    joey54321 Posts: 1,297
    So the lever feels firm and the brakes are effective once they bite, it does come back to the bar (and further than the rear brake), there is some of the pad left though I don't really have the experience to judge if it is a lot or not, maybe 1-2mm. I didn't know there was a minimum width of the rotors but they haven't seen that much use, I would be surprised if they were worn already.
  • paulbnix
    paulbnix Posts: 631
    I also have SRAM Rival Hydro and similar issues as you.

    I found the front brake worked wonderfully from the tops but the lever came too far back when I was on the drops.

    I cleaned out the caliper and made sure the pistons moved freely - didn't seem to fix the problem.

    I have some DiscoBrakes pads in the front and the return spring is very strong and wide open so I wondered if that was causing the pads to be pushed too far back. I bent the spring in and that didn't seem to fix the problem except if I bent it too far in I could get some rubbing.

    The solution I found in the end was to wind out the brake lever using the adjustment under the hood.
    The lever is much further out than it is on my rim braked bike but it seems to work ok because I can slip my fingers round the lever and pull it back. In this position the brakes are not being applied but are ready.
    If I'm setting off down a hill where I know I'm going to be braking from the drops I sometimes give the lever a pump which I think has the effect of moving the pads in a bit.