Brakes slightly moaning
08-17-2010, 10:23 AM
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My Ride: BMW
Model Year: 2006
A mechanic friend of mine just installed R1 Concept drilled\slotted rotors and hawk pads in my car. Everything brand new. The install went well and my friend didn't have a problem with it. Right after the install, we started the bedding process. Going up to 40mph, then slowing down to 10mph (no stopping) and then speeding up again. We did the cycle at least 4 times and even went up to 65 then slowing down again a couple of times to do more bedding. Throughout those times, I noticed that there is a slight moan when the car slows to about 20mph or 15mph. I don't know if I'm braking too hard, but to me it's my normal braking when coming to a stop at an intersection. It seems I have to brake earlier and softer to avoid the moan. No vibration on the steering wheel.
Is this normal? I've never had drilled\slotted rotors before so I'm just wondering if it's the brake pads just getting used to the rotors. Will it go away over time?
Is this normal? I've never had drilled\slotted rotors before so I'm just wondering if it's the brake pads just getting used to the rotors. Will it go away over time?
08-17-2010, 10:49 AM
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Basically it moans when coming to a stop. I don't THINK I'm braking too hard but I find that if I brake earlier and softer, there's no moaning. I'll drive around awhile and let you know. Right now I just put in less than 50 miles on the setup. I'll be gentle on braking to see if the moaning eventually subsides.
BTW, the rotors are install so that the slots (top of rotor) are leaning towards and pointing to the back of the car.
Driver side view: frontofcar //// backofcar
Passenger side view: backofcar \\\\ frontofcar
BTW, the rotors are install so that the slots (top of rotor) are leaning towards and pointing to the back of the car.
Driver side view: frontofcar //// backofcar
Passenger side view: backofcar \\\\ frontofcar
08-17-2010, 10:52 AM
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My Ride: Estoril Blue 440i GC
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Slotted (and drilled) rotors will be considerably noisier than stock.
I got plain slotted because I didn't want the noise of a drilled set. The slotted are quieter, but still noisy compared to stock. You'll have to live with it, I'm afraid - the penalty for having "better" brakes.
Mike
I got plain slotted because I didn't want the noise of a drilled set. The slotted are quieter, but still noisy compared to stock. You'll have to live with it, I'm afraid - the penalty for having "better" brakes.
Mike
08-17-2010, 10:52 AM
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My Ride: 2008 550I LOADED, all options except HUD and NV
They are supposed to go the other way around. The idea is that the slots remove excess dust from the pads 
Slotted rotors DO sound different, more like a zipper being pulled down quickly than moaning though. This is because of the air gap created by the slots, they are supposed to sound like that.
Slotted rotors DO sound different, more like a zipper being pulled down quickly than moaning though. This is because of the air gap created by the slots, they are supposed to sound like that.
08-17-2010, 11:12 AM
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They are supposed to go the other way around. The idea is that the slots remove excess dust from the pads
Slotted rotors DO sound different, more like a zipper being pulled down quickly than moaning though. This is because of the air gap created by the slots, they are supposed to sound like that.
Slotted rotors DO sound different, more like a zipper being pulled down quickly than moaning though. This is because of the air gap created by the slots, they are supposed to sound like that.
Really, it's backwards? I copied the 8th and 9th picture on this DIY thread:
https://5series.net/forums/topic/830...-the-calipers/
Here's a picture of the front passenger side:
08-17-2010, 11:51 AM
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My Ride: 2006 550i | Silver-Grey- A08 | Premium - Sport Package | Adaptive Headlights | Logic 7 w/ CD Changer | Bluetooth | Park Distance Control | Xenon Headlights | Comfort Access [s]Sprint Booster V1[/s] | K&N filter - Stock Box w/ Charcoal Filter Removed | Clear Side LED Markers | Matte Black Grilles | RPI Air Scoop | RPI 550i GT Exhaust | 12" Kicker w/ AMP | Headlight Euro Overlays | ACS Rep Roof\Trunk Spoilers |MTEC V2 Angel Eyes | 6000k HID Fog Lights | 19" VMR v710 Stag Wheels | Hankook Ventus V12 Evo K110 Tires | Debadged | LED Courtesy Door Lamps | Sprint Booster V2 | Painted Calipers | M pedals\shift knob | HID License Plate Bulbs | R1 Drilled\Slotted Rotors | Hawk HPS Brakes| ACS replica front lip |
That's how mine were install too. No issues.
08-17-2010, 11:58 AM
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Either way, slotted sound different from OEM, slotted and drilled sound different from slotted, it is kind of the way it is. You get performance products they are made for performance, not noise reduction. Have to balance what you want out of them. Also, if you are having to brake earlier then you are definitely doing something wrong, I have OEM rotors and Hawk pads, and I rarely start to brake before the start of the left turn lane. Try bedding them in again ( 12-14 runs of 60-10-60-10 ) see if that helps. I did this procedure with my brakes and they work flawlessly.
08-17-2010, 12:30 PM
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My Ride: Estoril Blue 440i GC
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You CAN get them the wrong way round.
I have EBC rotors, and I ummed and ahh'd about which way to fit them, and I'd just done one side when I saw that they were marked with a directional arrow. Yes, I'd got it on wrong! Still, it's a good thing that I noticed!
Mike
I have EBC rotors, and I ummed and ahh'd about which way to fit them, and I'd just done one side when I saw that they were marked with a directional arrow. Yes, I'd got it on wrong! Still, it's a good thing that I noticed!
Mike