mattscq

So I got to do my first proper descent (about -5-9% grade) and it was great, The road was closed to cars and sparsely populated with just a few groups of people and a few cyclists going up and down it. I got up to about 41 mph and the cornering was pretty controlled and everything was immensely fun.

There were a few areas when I had to pull the brakes to slow down a bit and at high speeds, it seemed to sometimes make a sort of ticking noise. The braking performance was spot on but I'm wondering what could be causing that. This is the first time I've heard it and it doesn't always happen.

They're Shimano Ultegra R8000 brakes on Ultegra rotors.

WhyFi

Noise when the brakes are hot isn't uncommon. My assumption is that the rotors expand with the heat, which accentuates any out-of-true, shrinks the clearances to nothing and causes minor contact, sometimes even when you're not braking. Clicking could just be a rough edge of a venting hole of something similar.

With my first set of finned IceTech rotors a few years ago, I noticed that the noise after heavy braking seemed to go away more quickly, so I took that as a sign that they actually were dissipating heat a little faster than my previous, all steel rotors.

Not a worry, though.

drewtk

Yep, I'd agree it's some sort of heat expansion issue. Pay attention to it but it doesn't sound like a cause for concern. You could always slowly rotate your wheel while the bike is stationary and confirm that the rotors aren't warped and that the pads aren't touching.

MoAlpha

On hard braking, the front caliper on my road bike emits a tick at the frequency of the cutouts in the rotor. Never looked into it and it's not nearly as annoying as the squeal from the rear when I get a load of oily sweat on it.

AdkMtnMonster

Those disc brake ticks are a statistics counter ticking off all of the crashes you avoided by running disc brakes vs 1600s technology rim brakes.