Anyone know anything about disc brakes?

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  • Yeah, I did that and sanded the pads but it started getting noisy again so now I'm going to try sanding+iso the discs but then using new pads.

  • Don't know if its been mentioned, but what combo rotors/callipers are you using? Some mixes are noisier than others. Mixing sram/shimano etc. Can you switch over or borrow some other brand rotors to test?

  • XTR calipers with a mix of cheaper Shimano rotors I think. Not sure of the pads. One set is deffo Shimano and the other set is something else.

  • Sandpapered and isopropyl'd the fuck out of the GrInbred rotors again and then put in new pads (Lifeline Orgasmic) and the squealing has gone for now.

  • Can anyone recommend what to do here? Spokes are very close to the caliper and do touch when centered in position. I can’t move it anymore to the right as it rubs the disc. It’s a Spyre caliper, do I need to go for a more narrow caliper?

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  • my avid bb7's are still working beautifully after 8 years of epping mud, ditto the jump bike's bb7's, still as good as i could wish for

  • Spyres are quite wide due to the mechanical double sided actuation. One solution is to use a bigger rotor which will give you a bit more room behind the caliper.

  • Can you fit 4-piston Shimano calipers to a road bike? Like, instead of the normal Ultregra flat mount BR-whatever caliper? What would it do? Explode? Snap your fork? Make stopping require less finger pressure?

  • nah should be fine

  • 'should be'

  • I had this issue when I had spyres. I used a washer between the hub and the fork drop out and a spacer to bring the disc slightly outboard in line with the caliper. Worked perfectly. Required a bit of trial and error to get the spacing perfect.

    Edit: I had QR and steel fork not carbon thru axle re. washer.

  • you are right, we need @snottyotter to say the same

  • Do they go bigger than 160mm??

  • Thanks, i'll give this a try.

  • I always wait until 3 people say "do it" on here and then I go ask on a proper bike forum...

  • From your photos, it looks like you have flat mount, so probably not. I didn't know whether you were using 140mm. If you're desperate, then you could also wind the inboard all the way out, so the disc isn't centered in the caliper but is still centered between pads. Or use a half worn pad on the inside. Or shim the rotor. I would prefer any of those solutions over shimming the hub end caps.

  • Yes its flat mount. I've just tried shimming the rotor which has helped. will wind the pads to see if that helps cheers.

  • Snap your fork?

    Seems unlikely. The front braking limit on a solo is always an endo, using "better" brakes just means it takes less lever force to tip you over the bars.

  • I've been running my grx with 4pot deores, all good, but only if you need IS/post mount, no 4pot flat mount Shimano brakes yet.

  • Hang on, what's the point of 4 pots anyway? They dissipate more heat or deal with water better or what? They move smoother?

    You're just applying the same force over double the area so power's the same shirley (for a given lever)

    I have 4 pots and I don't know why

  • 4 is more than 2.

  • I don't know. I read about someone using 4 piston brakes on an MTB to reduce hand fatigue or some shit and then thought "I wonder if the same can be done on road".

  • Hang on, what's the point of 4 pots anyway? You're just applying the same force over double the area

    In the idealised implementation, you're apply the force over the same area (same size master cylinder, twice as many caliper pistons each with half the area). The advantage is that the pad area is concentrated towards the outer rim of the rotor, so although all the forces are the same, the torque is slightly amplified as the mean radius of action is increased.

    If you have power-assist, you can apply the same force over an extended area, and if you can't increase the rotor diameter due to packaging issues, that's a good way to get a big increase in brake power. Neither applies to bicycles.

    The current Shimano 4-pots use differential pistons, with the leading piston being smaller. This means there's less force on the leading half of the pad, which is said to benefit modulation and eliminate chatter (noise)

    A minor benefit is that the radial depth of the rotor track is reduced, so the rotors can be slightly lighter. This is particularly evident with composite rotors, since you're cutting steel and adding aluminium, but even applies to monolithic steel rotors.

    The main benefit on a bicycle is that 4-pots just look cooler

  • 4-pots just look cooler


  • +1 for winding in the inboard pad.

    Then going shimano hydraulic.

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Anyone know anything about disc brakes?

Posted by Avatar for Sanddancer @Sanddancer