So what is the definitive answer about noisy Dura Ace rotors?

[roselend]

Some tips for Shimano road brakes from the proffesional peleton:

1: 140 front and back. The 160 warps a lot under heat from descending, 140 is less affected. XTR warps less than Dura-Ace. More sturdy construction.

2: Discs that warp under heat and heavy braking is normal, they always warp inwards to the hub. It will straighten out when cooling down again, this can happen quite fast.

3: Brakes that squeel are not normal, squeeling is a indication that there is something wrong.

4: Make sure your flatmounts of your frame are straight. 80% of frames coming out of factory are not perfectly straight. What happens is that the caliper is at a slight angle. Every time you brake if forces the disc in a unnatural angle and this makes noise. Your pads will wear out crooked. When the caliper is not straight and you do some heavy braking the disc can warp inward and actually start dragging on the alumunium of the caliper, instead of dragging on the pad where it should drag. This occurence has a very distinctive metal on metal noise.

5: Use a soft brake pad. Shimano K03S for example, this one makes less noise. Braking feels a bit softer. It's a cheaper version pad. A lot of Pro Teams use it.

5: Degrease your new pads and discs with 96% alcochol BEFORE wearing them in.

6: Always wear in your pads AND dics. On a machine, or on a stretch of downhill road. Replicate normal braking. 10 sec on, 5 sec off, 10 sec on, 5 sec off etc. The point is to have the pad material on both pad and disc. This creates a much more effiecent braking surface with less heat being generated.

7: Never ever touch your pads and disc with your hands. One greasy finger is enough to cause problems.

8: Never ever clean your pads and discs with a sponge, towel, cloth etc. This one can also be greasy, although it sometimes can't be seen by the naked eye. Just soap and rinse off with water is enough. A disc doesn't want to be spotless clean. Spottles clean = smooth = more heat being generated.

9: Never use degreaser on pads and discs. You're also washing off the pad material on the disc. This is the stuff that needs to stay on for optimal braking. Soap is no problem but can leave a thin film on the pads and disc, this brakes of easily after 1 or 2 times. It's no problem.

10: Replace pads more often! When they start making noise there's probaly some oil or grease on them.

11: Organic pad material can be burned easliy from heavy braking, the pads wil glaze. Replace.

12: Disc can not burn, but the defenitely can warp and be permanelty warped from heavy braking. If it's impossible to straighen again. Replace.

13: When you replace a disc, always replace the pads too.

14: For a quick fix, if you dont have new pads in house you can always try to sand off the 'contaminated' top layer of the brake pad. This sometimes works if it's not too bad.

15: Never do a full bleed right away when you're having problems with your Shimano brakes. The problem is most likely air, which causes spungy feeling brakes. Air bubbles can be removed from the top. New oil also has micro bubbles of air inside.

16: Check your oil reguarly with the bleeding pot on top of the shifter. Micro air bubbles inside the oil, caliper or shifter can clog up to 1 big air bubble. Tap the brakes and tilt the bike forward and backwards. A air bubble can be caught behind the oil chambers inside the shifter. If done correctly all air bubbles should come out at the top.

17: If the oil at the top coming out is black colored your oil is contaminated with water. Water can come in through all linkages and pistons. Water compresses, oil does not. So the water causes spungy brakes or pistons not coming back properly. Water inside the hose can also evaporate under heavy braking, which creates sudden new air bubbles. Which can be quite dangerous.

18: Dirty pistons eventually will clog up and they will stop working or returning inside the caliper. The best way to clean a piston is by lubracting it in it's own mineral oil. You can do this by pushing back the pistons inside the caliper with a tool and brake a few times again, repeat until clean.

Hope this helps you guys out a bit.

[Lewn777]

Some tips for Shimano road brakes from the proffesional peleton:

1: 140 front and back. The 160 warps a lot under heat from descending, 140 is less affected. XTR warps less than Dura-Ace. More sturdy construction.

2: Discs that warp under heat and heavy braking is normal, they always warp inwards to the hub. It will straighten out when cooling down again, this can happen quite fast.

3: Brakes that squeel are not normal, squeeling is a indication that there is something wrong.

4: Make sure your flatmounts of your frame are straight. 80% of frames coming out of factory are not perfectly straight. What happens is that the caliper is at a slight angle. Every time you brake if forces the disc in a unnatural angle and this makes noise. Your pads will wear out crooked. When the caliper is not straight and you do some heavy braking the disc can warp inward and actually start dragging on the alumunium of the caliper, instead of dragging on the pad where it should drag. This occurence has a very distinctive metal on metal noise.

5: Use a soft brake pad. Shimano K03S for example, this one makes less noise. Braking feels a bit softer. It's a cheaper version pad. A lot of Pro Teams use it.

5: Degrease your new pads and discs with 96% alcochol BEFORE wearing them in.

6: Always wear in your pads AND dics. On a machine, or on a stretch of downhill road. Replicate normal braking. 10 sec on, 5 sec off, 10 sec on, 5 sec off etc. The point is to have the pad material on both pad and disc. This creates a much more effiecent braking surface with less heat being generated.

7: Never ever touch your pads and disc with your hands. One greasy finger is enough to cause problems.

8: Never ever clean your pads and discs with a sponge, towel, cloth etc. This one can also be greasy, although it sometimes can't be seen by the naked eye. Just soap and rinse off with water is enough. A disc doesn't want to be spotless clean. Spottles clean = smooth = more heat being generated.

9: Never use degreaser on pads and discs. You're also washing off the pad material on the disc. This is the stuff that needs to stay on for optimal braking. Soap is no problem but can leave a thin film on the pads and disc, this brakes of easily after 1 or 2 times. It's no problem.

10: Replace pads more often! When they start making noise there's probaly some oil or grease on them.

11: Organic pad material can be burned easliy from heavy braking, the pads wil glaze. Replace.

12: Disc can not burn, but the defenitely can warp and be permanelty warped from heavy braking. If it's impossible to straighen again. Replace.

13: When you replace a disc, always replace the pads too.

14: For a quick fix, if you dont have new pads in house you can always try to sand off the 'contaminated' top layer of the brake pad. This sometimes works if it's not too bad.

15: Never do a full bleed right away when you're having problems with your Shimano brakes. The problem is most likely air, which causes spungy feeling brakes. Air bubbles can be removed from the top. New oil also has micro bubbles of air inside.

16: Check your oil reguarly with the bleeding pot on top of the shifter. Micro air bubbles inside the oil, caliper or shifter can clog up to 1 big air bubble. Tap the brakes and tilt the bike forward and backwards. A air bubble can be caught behind the oil chambers inside the shifter. If done correctly all air bubbles should come out at the top.

17: If the oil at the top coming out is black colored your oil is contaminated with water. Water can come in through all linkages and pistons. Water compresses, oil does not. So the water causes spungy brakes or pistons not coming back properly. Water inside the hose can also evaporate under heavy braking, which creates sudden new air bubbles. Which can be quite dangerous.

18: Dirty pistons eventually will clog up and they will stop working or returning inside the caliper. The best way to clean a piston is by lubracting it in it's own mineral oil. You can do this by pushing back the pistons inside the caliper with a tool and brake a few times again, repeat until clean.

Hope this helps you guys out a bit.

^^^^This is excellent, needs its own sticky^^^^

[tommyboyo]

Some tips for Shimano road brakes from the proffesional peleton:

1: 140 front and back. The 160 warps a lot under heat from descending, 140 is less affected. XTR warps less than Dura-Ace. More sturdy construction.

2: Discs that warp under heat and heavy braking is normal, they always warp inwards to the hub. It will straighten out when cooling down again, this can happen quite fast.

3: Brakes that squeel are not normal, squeeling is a indication that there is something wrong.

4: Make sure your flatmounts of your frame are straight. 80% of frames coming out of factory are not perfectly straight. What happens is that the caliper is at a slight angle. Every time you brake if forces the disc in a unnatural angle and this makes noise. Your pads will wear out crooked. When the caliper is not straight and you do some heavy braking the disc can warp inward and actually start dragging on the alumunium of the caliper, instead of dragging on the pad where it should drag. This occurence has a very distinctive metal on metal noise.

5: Use a soft brake pad. Shimano K03S for example, this one makes less noise. Braking feels a bit softer. It's a cheaper version pad. A lot of Pro Teams use it.

5: Degrease your new pads and discs with 96% alcochol BEFORE wearing them in.

6: Always wear in your pads AND dics. On a machine, or on a stretch of downhill road. Replicate normal braking. 10 sec on, 5 sec off, 10 sec on, 5 sec off etc. The point is to have the pad material on both pad and disc. This creates a much more effiecent braking surface with less heat being generated.

7: Never ever touch your pads and disc with your hands. One greasy finger is enough to cause problems.

8: Never ever clean your pads and discs with a sponge, towel, cloth etc. This one can also be greasy, although it sometimes can't be seen by the naked eye. Just soap and rinse off with water is enough. A disc doesn't want to be spotless clean. Spottles clean = smooth = more heat being generated.

9: Never use degreaser on pads and discs. You're also washing off the pad material on the disc. This is the stuff that needs to stay on for optimal braking. Soap is no problem but can leave a thin film on the pads and disc, this brakes of easily after 1 or 2 times. It's no problem.

10: Replace pads more often! When they start making noise there's probaly some oil or grease on them.

11: Organic pad material can be burned easliy from heavy braking, the pads wil glaze. Replace.

12: Disc can not burn, but the defenitely can warp and be permanelty warped from heavy braking. If it's impossible to straighen again. Replace.

13: When you replace a disc, always replace the pads too.

14: For a quick fix, if you dont have new pads in house you can always try to sand off the 'contaminated' top layer of the brake pad. This sometimes works if it's not too bad.

15: Never do a full bleed right away when you're having problems with your Shimano brakes. The problem is most likely air, which causes spungy feeling brakes. Air bubbles can be removed from the top. New oil also has micro bubbles of air inside.

16: Check your oil reguarly with the bleeding pot on top of the shifter. Micro air bubbles inside the oil, caliper or shifter can clog up to 1 big air bubble. Tap the brakes and tilt the bike forward and backwards. A air bubble can be caught behind the oil chambers inside the shifter. If done correctly all air bubbles should come out at the top.

17: If the oil at the top coming out is black colored your oil is contaminated with water. Water can come in through all linkages and pistons. Water compresses, oil does not. So the water causes spungy brakes or pistons not coming back properly. Water inside the hose can also evaporate under heavy braking, which creates sudden new air bubbles. Which can be quite dangerous.

18: Dirty pistons eventually will clog up and they will stop working or returning inside the caliper. The best way to clean a piston is by lubracting it in it's own mineral oil. You can do this by pushing back the pistons inside the caliper with a tool and brake a few times again, repeat until clean.

Hope this helps you guys out a bit.

Brilliant and superbly detailed post, although I can't help feeling that you are making disc brakes sound WAY more complicated/intimidating than they really are!!

When I made the switch last year I came in with no experience, having ridden only rims all my life. I was quite nervous, as I had read a lot of things like this, but really they are a piece of piss to maintain once you get to grips with the basic!!

Mine have been flawless with just the odd check for air bubbles via the caliper port and regular light cleaning etc...

Only issue is the ticking after heavy braking, which is why I started this thread and think it has probably near enough been confirmed that it is the DA rotors causing the issue and that it is not even really a 'problem', but just super annoying

[rollinslow]

Which pads are you using? From what you describe I think the pads are the likely culprit - there comes a point (temperature) at which the pad/rotor interface operates in a stick/slip manner and that vibration is the starting point for the noise.

I'll agree that discs for road bikes are definitely not good enough, yet. Most of the time, my current setup (DA calipers/Swissstop Catalyst rotors/various pads) is good, but under heavy use in the dry or general use in the wet, not good enough! Too much noise.

Im using stock Shimano L03A resin pads. Never seen even the slightest amount of water, oil or even fingers.

[rollinslow]

There have been a few compound changes in the DA pads. The latest ones are much quieter and stop well.

are these still the L03A pads?

[tjvirden]

There have been a few compound changes in the DA pads. The latest ones are much quieter and stop well.

are these still the L03A pads?

Yes; L03A uses the newest compound.

If you're getting howling in the dry, then I think there must be some contamination of the pad. In my experience, that really can happen without any obvious cause - I know you've stated that there's been no water, grease, fingers etc on the discs/pads. The only other likely possibility I can think of is "dry" conditions, but high humidity - I've also experienced howling rim brakes in that circumstance.

I have restored pads and discs to normal operation (from howling in the dry) by sanding both with fine sandpaper (320 grit I think), removing the dust and then carefully cleaning with IPA (alcohol) - in my case, I could see contamination on the surface of the disc and IPA on its own would not remove that. It can be impossible to see contamination on the pad.

[rollinslow]

There have been a few compound changes in the DA pads. The latest ones are much quieter and stop well.

are these still the L03A pads?

Yes; L03A uses the newest compound.

If you're getting howling in the dry, then I think there must be some contamination of the pad. In my experience, that really can happen without any obvious cause - I know you've stated that there's been no water, grease, fingers etc on the discs/pads. The only other likely possibility I can think of is "dry" conditions, but high humidity - I've also experienced howling rim brakes in that circumstance.

I have restored pads and discs to normal operation (from howling in the dry) by sanding both with fine sandpaper (320 grit I think), removing the dust and then carefully cleaning with IPA (alcohol) - in my case, I could see contamination on the surface of the disc and IPA on its own would not remove that. It can be impossible to see contamination on the pad.

I've wondered about humidity effects on noise as well. In the mornings, humidity here can be 90% in summer. I'll throw the XTR's and get a direct comparison back here soon once I do the re-bedding procedure, etc.

[Luca199]

Hi everyone, I changed the DA rotors to SRAM Centerline XR (160mm both front and rear) last Saturday. Run them on Shimano Ultegra braking system and Shimano L04C (sintered) pads. The installation was okay, no rubbing or ither issues. Bedded them in as per usual process, took me 20-30 minutes to do a good job and ensure everything was fine. The following day (Sunday) went on a hilly ride, first 60km everything was smooth, no noise whatsoever or very little (which I thought would be given by the metal pads). The second half of the ride I started suffering from noise on the rear. Front was okay and stayed okay until the end of the ride, but the rear started making a noise on every brake, even in the flat... it's like a horn/harmonic noise, and every now and then I would also get the occasion ticking/rubbing noise which would then disappear... I don't know what to do anymore just changed rotors and the problem is still there..... it's very strange that it developed halfway through the ride, and only on the rear, not front. Everything was dry so there can not be any contamination. Tried the bike again this morning on flat easy laps in a park, even cleaned the rear pads and rotors just to be sure, and the noise now is still there not even on descents, just every time I brake, unless it's a very soft brake at traffic light, when I don't hear anything...

I have just bought some Swissstop disc 34 RS (organic compound) which will be delivered later this week. Should I try and install them and run them in the same SRAM centerline rotors, which by now would have some metal compound on them, or should I install on a brand new set of rotor? Was thinking of buying the campagnolo afs rotor with steel spider (or rotor 03 with the aluminium one), but if I can save some money there, that'd be nice... however, if the resin pads can have trouble running on a surface already affected by metal pads, I'll change the rotor too.

Thanks for any help.. I'm lost here

[rollinslow]

Hi everyone, I changed the DA rotors to SRAM Centerline XR (160mm both front and rear) last Saturday. Run them on Shimano Ultegra braking system and Shimano L04C (sintered) pads. The installation was okay, no rubbing or ither issues. Bedded them in as per usual process, took me 20-30 minutes to do a good job and ensure everything was fine. The following day (Sunday) went on a hilly ride, first 60km everything was smooth, no noise whatsoever or very little (which I thought would be given by the metal pads). The second half of the ride I started suffering from noise on the rear. Front was okay and stayed okay until the end of the ride, but the rear started making a noise on every brake, even in the flat... it's like a horn/harmonic noise, and every now and then I would also get the occasion ticking/rubbing noise which would then disappear... I don't know what to do anymore just changed rotors and the problem is still there..... it's very strange that it developed halfway through the ride, and only on the rear, not front. Everything was dry so there can not be any contamination. Tried the bike again this morning on flat easy laps in a park, even cleaned the rear pads and rotors just to be sure, and the noise now is still there not even on descents, just every time I brake, unless it's a very soft brake at traffic light, when I don't hear anything...

I have just bought some Swissstop disc 34 RS (organic compound) which will be delivered later this week. Should I try and install them and run them in the same SRAM centerline rotors, which by now would have some metal compound on them, or should I install on a brand new set of rotor? Was thinking of buying the campagnolo afs rotor with steel spider (or rotor 03 with the aluminium one), but if I can save some money there, that'd be nice... however, if the resin pads can have trouble running on a surface already affected by metal pads, I'll change the rotor too.

Thanks for any help.. I'm lost here

I think here you somehow got contaminated pads on the rear. I would clean the disc with IPA and sand the pads. No need for new rotors and pads now. The sintered pads will be louder than resin.

[rollinslow]

As an update on swapping from DA rotors to XTR it was 90F outside and I did a 15min bed in etc. the same hill that produced the worst braking sounds I've ever heard was gone.

I still need to see if the XTR truly resist warping compared to DA but today seems promising.

[tommyboyo]

So i swapped out my DA's to XTR last week.

Done 300 odds miles now. Very hot most days and lots of heavy braking into junctions off descents etc...

Bye by noise. Literally silent, not one peep. Also, the braking is better (or could be a placebo now the sound is gone!!)

Interesting that the XTR style rotors seem to be stock for the next gen stuff in development right now, so shimano must have realised the issue with the current DA design I imagine.

[petersparks]

Some tips for Shimano road brakes from the proffesional peleton:

1: 140 front and back. The 160 warps a lot under heat from descending, 140 is less affected. XTR warps less than Dura-Ace. More sturdy construction.

2: Discs that warp under heat and heavy braking is normal, they always warp inwards to the hub. It will straighten out when cooling down again, this can happen quite fast.

3: Brakes that squeel are not normal, squeeling is a indication that there is something wrong.

4: Make sure your flatmounts of your frame are straight. 80% of frames coming out of factory are not perfectly straight. What happens is that the caliper is at a slight angle. Every time you brake if forces the disc in a unnatural angle and this makes noise. Your pads will wear out crooked. When the caliper is not straight and you do some heavy braking the disc can warp inward and actually start dragging on the alumunium of the caliper, instead of dragging on the pad where it should drag. This occurence has a very distinctive metal on metal noise.

5: Use a soft brake pad. Shimano K03S for example, this one makes less noise. Braking feels a bit softer. It's a cheaper version pad. A lot of Pro Teams use it.

5: Degrease your new pads and discs with 96% alcochol BEFORE wearing them in.

6: Always wear in your pads AND dics. On a machine, or on a stretch of downhill road. Replicate normal braking. 10 sec on, 5 sec off, 10 sec on, 5 sec off etc. The point is to have the pad material on both pad and disc. This creates a much more effiecent braking surface with less heat being generated.

7: Never ever touch your pads and disc with your hands. One greasy finger is enough to cause problems.

8: Never ever clean your pads and discs with a sponge, towel, cloth etc. This one can also be greasy, although it sometimes can't be seen by the naked eye. Just soap and rinse off with water is enough. A disc doesn't want to be spotless clean. Spottles clean = smooth = more heat being generated.

9: Never use degreaser on pads and discs. You're also washing off the pad material on the disc. This is the stuff that needs to stay on for optimal braking. Soap is no problem but can leave a thin film on the pads and disc, this brakes of easily after 1 or 2 times. It's no problem.

10: Replace pads more often! When they start making noise there's probaly some oil or grease on them.

11: Organic pad material can be burned easliy from heavy braking, the pads wil glaze. Replace.

12: Disc can not burn, but the defenitely can warp and be permanelty warped from heavy braking. If it's impossible to straighen again. Replace.

13: When you replace a disc, always replace the pads too.

14: For a quick fix, if you dont have new pads in house you can always try to sand off the 'contaminated' top layer of the brake pad. This sometimes works if it's not too bad.

15: Never do a full bleed right away when you're having problems with your Shimano brakes. The problem is most likely air, which causes spungy feeling brakes. Air bubbles can be removed from the top. New oil also has micro bubbles of air inside.

16: Check your oil reguarly with the bleeding pot on top of the shifter. Micro air bubbles inside the oil, caliper or shifter can clog up to 1 big air bubble. Tap the brakes and tilt the bike forward and backwards. A air bubble can be caught behind the oil chambers inside the shifter. If done correctly all air bubbles should come out at the top.

17: If the oil at the top coming out is black colored your oil is contaminated with water. Water can come in through all linkages and pistons. Water compresses, oil does not. So the water causes spungy brakes or pistons not coming back properly. Water inside the hose can also evaporate under heavy braking, which creates sudden new air bubbles. Which can be quite dangerous.

18: Dirty pistons eventually will clog up and they will stop working or returning inside the caliper. The best way to clean a piston is by lubracting it in it's own mineral oil. You can do this by pushing back the pistons inside the caliper with a tool and brake a few times again, repeat until clean.

Hope this helps you guys out a bit.

Thank You. Very useful tips. They will surely help me more than a bit

[GregR]

I had noisy discs at the beginning of this season. They were quiet all last year, and I had done a disc and pad replacement on the front. On the back, just cleaned the caliper and disc with alcohol. (not the pads.) Tried everything, what worked was hard braking from 50 kmh or so. One wheel at a time. Got everything nice and hot, and the noise was gone. KO3Ti pads. I read that road bikes are susceptible to squeal because we tend to brake lightly a lot, thus glazing the pads. Hard braking burns the glaze off. YMMV.

[GregR]

Some tips for Shimano road brakes from the proffesional peleton:

1: 140 front and back. The 160 warps a lot under heat from descending, 140 is less affected. XTR warps less than Dura-Ace. More sturdy construction.

...

5: Use a soft brake pad. Shimano K03S for example, this one makes less noise. Braking feels a bit softer. It's a cheaper version pad. A lot of Pro Teams use it.

5: Degrease your new pads and discs with 96% alcochol BEFORE wearing them in.
...

For 1, if you are not in the pro peleton (or racing) you should use discs that are the correct size for your weight and the riding that you do.
Same for the first 5, if you are doing a lot of long hard descents then get a suitable pad.
For the 2nd 5, what is the process for this?

[LanceLegstrong]

1: 140 front and back.

cries in 85kg

Joking aside, great tips. Just can't use 140 safely on the front.

And agree with using XTR rotors. They're been great. Silent 99% of the time and any "ting ting" after a descent I can stop by a few quick sharp brake pulls.