Two hot brake questions: EBC sintered pads whoosh noise, and either rotor or bearing noise.

[Allen42]

Question 1: My bike has always had a noise that I'm pretty sure is pad rub, but only after the brakes are hot. This occurs only when not braking, and is easy to hear at slow speeds, especial when running down the alley behind my house with the noise bouncing off the fences. This noise did not stop when I replaced the pads. (next question) It is rhythmic, and speeds up or decreases with the bike speed. In my mind, it's a rotor rubbing or a bearing of some sort. It is not a high pitched squeal, more of a rubbing noise, somewhat similar to the braking noise described below.

Question 2: About 1,200 miles ago, I replaced all pads with EBC fully sintered pads, and hand beveled the front and rear edges. Now when I brake, the pads make a whirring, whooshing, or a throaty ssshhhshshshsh noise that was not there with OEM brakes. (Hard to describe.) Again, this also only happens when they are hot, and is consistent, it does not pulse or pull any direction. I assume this is just the sound these pads make, but it's very noticeable, so I wanted to run it past you experts. I used the pink no squeal stuff, and anti-seize, and think I did everything correctly including taking them to a parking lot and hot-bedding them as BajaRon has described.

Any feedback on these two items?

 

[Peter Aawen]

I'd think both of these are most likely just the pads not quite pushing fully clear of the discs on release, and if your discs aren't obviously over-heating, it's prabably nothing to worry about.

However, if you are really concerned, you could try raising the front wheels of the bike (engine & ignition off, rear wheel chocked, on stable stands) so that the front wheels can spin freely, and listen carefully as you spin each wheel by hand. There's a very good chance that you'll hear the same sort of noise, if not initially, then possibly after spinning the wheel a bit and then stopping it using the brake pedal, then spinning again. It's quite common and if it's a fairly steady but faint noise, rather than a continuous loud and abrasive noise teamed with noticeable resistance to turning the wheel OR a distinct pulse of increased noise teamed with the wheel actively resisting spinning, it's not generally anything to worry about.

However, if you DO hear that noise somewhat MORE than 'faintly' &/or in that distinctive 'more noise, marked resistance' pulsing manner, don't panic just yet!! Simply grasp the wheel top and bottom and not savagely just twist/rattle it a little bit (pull out on the top, push in on the bottom; then alternate and push in on the top, pull out on the bottom) a couple of times; then still holding the wheel in the same place, rotate the wheel until your hands are horizontally level and give it a similar little bit of twist/rattling. Once you've done that, which should serve to minutely push the pads juuuust clear of the discs, try spinning the wheel again and listen for any reduction in noise/feel for any free-er spinning. IF that 'MORE than faint' noise &/or the 'more noise, marked resistance' has reduced &/or completely gone, then you're good to go! BUT, if it hasn't reduced &/or gone, you might want to investigate further!

That 'investigate further' could entail, amongst other things, checking the lug nuts for even torquing (to avoid twisting the wheel on the hub and the pads on the disc); removing the wheel and checking the calipers for free movement, making sure the slides are lightly lubed and aren't grabbing or holding; checking that the pads are properly mounted; looking for excessive radial run-out in the disc while rotating; making sure that the pedal/hydraulic system pressure is actually releasing when you take your foot off the brakes; and basically investigating to so see WHY the pads aren't juuuuust clearing the discs when the brakes are released.

But seriously, if you're only hearing this as a slight noise in those conditions where it's likely at its worst or being reflected back at you and your discs/pads aren't showing signs of excessive heating (WARNING - DO NOT try touching a 'recently noisy' disc with anything attached to your body, ie. especially NOT bare skin!! Not unless you get off on losing said skin &/or the pain of deep burns anyway!! ) then I'd suggest that you just...


RIDE MORE, WORRY LESS!!

Ps: You might also want to check out some of the 'Similar threads' listed below.

 

[Allen42]

Thanks Peter. That is my next test, get it up on stands as quickly as possible after a ride when they are hot. I was really just hoping to have some folks chime in with "that's the normal EBC sound, nothing to worry about" for the "when braking" question, and getting it up on stands when hot for the when not braking rhythmic noise. I do torque my lugnuts to proper spec, and in a star pattern when possible.

 

[Cobranut]

Drilled/slotted discs often have a characteristic sound, usually a whirring or humming under light braking.
I even hear it on my cars that are so equipped.
Try this. Ride a couple miles without using the brakes, and stop with very minimal braking.Then check the brake disc temp with an IR temp gun, or holding the back of your hand near the disc. Being warm to the touch is normal, but if excessively hot, you need to check for a stuck caliper or slide bracket.