rottingcat

iTrader: (3)

Hey guys just replaced my brakes with rebuilt OEM brembos, hawk HPS 5.0 pads and z1 front 2 piece and z1 normal rears both slotted.


i had trouble bleeding brakes with the motive bleeder and the third try i got the brakes to work...but still felt soft and spongy. i decided to follow the bed in procedure
brakes feel fine but i have a humming noise under moderate to heavy braking when i am going above 40MPH
the noise cuts out if i am going slower than that.
at high speeds the hum is gradually louder and i feel a resonating/vibration into the cabin.

do you guys think this is a warped rotor? should i bleed the brakes until i get a proper pedal feel/no air?
or is it a wheel bearing...

The Swede

I would bleed the brakes properly first. And make sure you put everything on correctly. Then do another break in. Do the simple things first.

Is the vibration pulsating in relation to wheel speed? If so I suspect a warped rotor.

rottingcat

iTrader: (3)

yeah it's louder at higher speeds...i will update after bleeding brakes again i'm 100% sure i put everything in right. might have to contact z1...maybe i should have went with stoptech lol

dcains

iTrader: (15)

With the Brembo system properly bled, and with pads properly bedded, the brake pedal should be very firm. I don't think that's the source of your noise, though. Clearance between the dust shields and rotors is pretty small, so maybe you slightly bent one of the shields while replacing the rotors? I'd check in that area. Also, some rotors are just plain noisy, believe it or not. I had a set of EBC slotted rotors on my BMW, and I finally had to change them out due to the noise they made. They did make a sort of hum at high speeds when the brakes were not applied.

rottingcat

iTrader: (3)

instead of trimming my dust shields i simply bent them back with vice grips they are not touching the rotor but the clearance is pretty minimal, should i have cut them? i assumed since the rotor does not move in those directions it would be fine

i called z1 and spoke with ron, he said the rotors should not be making those noises and i should check my installation and attempt to bed in again...so will do that this weekend

dcains

iTrader: (15)

Man, that's horrible, and now I'm even think more that's the problem. Buy yourself a cheap angle-grinder and cut the lips off properly. It took me all of 5 minutes on mine, and it looks original after I touched up the edges with some black paint. Even if no one will ever see it, I know it was done right. and that's the only way to be.

This is the one I used, and it would cut up an entire car with no problems:


And blades: