Disk brake help SRAM

Itf_harry.s
Itf_harry.s Posts: 3
edited May 2018 in Cyclocross
So I’ve just bought a Giant TCX advanced SX and I noticed the front disk brakes didn’t work very well ( after breaking in screeching and lack of power, not being able to lift the back wheel in full force braking) I took it back to the shop where they replaced them with new (different) ones. These also don’t seem to work very well and are also screeching. I am very new to disk brakes as I’ve came from a race bike with rim brakes although I have ridden disks before and been very impressed with the power. What could be causing this? (bearing in mind they are hydraulic disk brakes)

Comments

  • Thigh_burn
    Thigh_burn Posts: 489
    Was it wet? If so, that's the screeching - it's a bit of a nightmare on discs.

    As for the not gripping well, they usually need some bedding in. It's been a few years since I bought my bike, but I think they recommended about 100 miles of taking it relatively easy on the brakes, and then they'll be fine.
  • They were dry, bike shop don’t seem to know what’s causing the power loss. They recommended tightening up the spikes to stop the noise. and to come back at the end of the week if it’s still bad.
  • haydenm
    haydenm Posts: 2,997
    They were dry, bike shop don’t seem to know what’s causing the power loss. They recommended tightening up the spikes to stop the noise. and to come back at the end of the week if it’s still bad.

    Spikes? Screeching is usually from the pads vibrating in the caliper, happens more in the wet or with contaminated pads. With a new set of pads you want to do a few descents before they become bedded in.

    What do you mean by not being able to lift the rear wheel under braking?
  • veronese68
    veronese68 Posts: 27,297
    To bed brakes in quickly get up to speed and brake hard, but not to a complete stop, then back up to speed and do it again. Keep repeating this and you should find the braking improves markedly after a few goes. Easiest to do it on a long downhill but getting up to speed, braking hard but not stopping up to a dozen times usually does the job.
    Surprised the bike shop didn't try that before replacing stuff.