rotor warping on disc brakes

[Ming the Merciless]

You go 40mph down hill on a tandem?? You are pretty brave!!

That’s pretty slow downhill for a tandem.

 

[Dogtrousers]

I have TRP Spyres on a QR wheeled bike (and I had the same before on two other bikes), so not sure why that’s an issue?

QRs?

Newfangled nonsense. What's wrong with wheel nuts?

 

[fritz katzenjammer]

When we get a bike through the shop which has a rubbing brake the first thing I do is put the bike on the floor, open the quick release and let the weight of the bicycle centre the wheel, that cures the problem quite often. You just can’t reliably centre a wheel in a stand or with the bike inverted.

 

[cyberknight]

When we get a bike through the shop which has a rubbing brake the first thing I do is put the bike on the floor, open the quick release and let the weight of the bicycle centre the wheel, that cures the problem quite often. You just can’t reliably centre a wheel in a stand or with the bike inverted.

thats what i do , even then it generally needs adjustment to get a decent bite

 

[Peter Salt]

Rotors warping isn't really something unusual. Truth to the matter is, bicycle rotors are just to thin and flimsy - and the manufacturers know it. Producing something that would actually work would make it significantly heavier and be bad for marketing, so they don't. Much easier to tell people they're using their brakes wrong - well, with all due respect, if you're going down a 20% gradient with potholes and occasional gravel (i.e. half of British hills), good luck with not occasionally dragging your brakes.

 

[fritz katzenjammer]

Rotors warping isn't really something unusual. Truth to the matter is, bicycle rotors are just to thin and flimsy - and the manufacturers know it. Producing something that would actually work would make it significantly heavier and be bad for marketing, so they don't. Much easier to tell people they're using their brakes wrong - well, with all due respect, if you're going down a 20% gradient with potholes and occasional gravel (i.e. half of British hills), good luck with not occasionally dragging your brakes.

The hardness of the material used varies greatly as well. I always recheck the rotors before releasing a machine. It’s not rare to find that rotors which have been corrected have returned to their previously warped state half an hour later and require additional work before the bike can go.

I yes, I assume that some will relax again and be dragging two hours later when the customer hits the road. It all boils down to initial component quality. During Covid, before I was with Trek, I saw shipments of bikes with three differing makes of brakes on the same model of machine, it was all the manufacturers could do to get parts to build bikes, only now are we getting truly caught up with this issue.

Thankfully there’s an amazing number of cyclists who will happily ride for miles with dragging brakes and half inflated tires. It’s easy to look good when all the bike needed was to have it’s tires pumped up and a wheel corrected in the dropouts… “gee, thanks.. the bikes is so much faster now!”

 

[Ajax Bay]

bicycle rotors are just too thin and flimsy - and the manufacturers know it. Producing something that would actually work would make it significantly heavier and be bad for marketing,

Yeah, all those pro cycling teams don't have brakes that "actually work". Right!

 

[Peter Salt]

Yeah, all those pro cycling teams don't have brakes that "actually work". Right!

I think you've slightly exaggerated here. When referring to 'not working' I meant it in the context of this topic - i.e. discs warping. Not actually not being able to stop

I don't think you're comparing apples to apples here. Pro team mechanics will adjust the brakes and likely swap pads after every other stage, every day if there were significant descents. Pro riders will also brake in a more on/off manner to maximise speed through corners on smooth tarmac - a bit different to dodgy British descents. Still, brake rub and noise is not uncommon in the pro peloton.

 

[FishFright]

Rotors warping isn't really something unusual. Truth to the matter is, bicycle rotors are just to thin and flimsy - and the manufacturers know it. Producing something that would actually work would make it significantly heavier and be bad for marketing, so they don't. Much easier to tell people they're using their brakes wrong - well, with all due respect, if you're going down a 20% gradient with potholes and occasional gravel (i.e. half of British hills), good luck with not occasionally dragging your brakes.

Only on the cheapest and nastiest Chinese tat. Although I replaced a lot of crappy ones when working in bike recycling they were all BSO level bikes. In 25 years of running decent disk brakes I've never had one rotor warp.

 

[ExBrit]

Cos I’m fat and ride down big hills… rims don’t stop me!

Either your picture and KOMs are really old or Drago wins the fat fecker award. Drago - how many KOM's you got?