[CadolinaRipr]

Would be interesting to know/see if all the other cases of this same noise and issue all had the same pads or not.

[gcmak]

Originally Posted by kyrix1st

Very interesting. Assuming those two use the same semi-metallic composition, solid ones (without the line in the middle) should produce better braking due to having more friction surface.
On the other hand, the "split" brake pads are generally known to be quieter, so more comfort oriented.

Correct and the weights on the split pad means it's dampened to reduce noise. We've seen both blue and red caliper cars on track stock, so both seem similarly capable but it could matter if we're splitting hairs. Hoping a shop or someone can do some back to back testing, for science!

[aerobod]

Originally Posted by kyrix1st

Very interesting. Assuming those two use the same semi-metallic composition, solid ones (without the line in the middle) should produce better braking due to having more friction surface.
On the other hand, the "split" brake pads are generally known to be quieter, so more comfort oriented.

I think it would be a negligible difference, any increased area would be offset by reduced pad cooling in the centre, potentially decreasing overall brake efficiency under hard use. The biggest effect could be on brake noise. I’ve run full area road oriented pads and higher performance grooved track pads on the Caterham, the pad friction coefficient differences hid any effect of groove or no groove.

[baron95]

Well, I have a set with weights and groove coming to me via eBay. And I ordered the red M Performance caliper on my G87 which should come with the solid/no-weights pads. I should run through them fairly quickly.

The only prob is that my car is still in Mexico and track season is coming to a close in New England/NE. If only BMW could get my car out of the port - oh, well.


P.S. The center grove should aid marginally in pad cleanup and gas venting, so may have slightly better fade resistance, but it is probably a marginal benefit.

[DCC]

Am I reading correctly that the pads on the blue caliper are different than the ones on the red caliper option?


This is unusual to say the least unless the source of the calipers/pads are from different vendors (which is still odd), and this is resulting in many more cars with red calipers having brake noise issues.

[fcman]

I have the blue calipers and have split pads. The verbage on the builder makes it seem like both pads/rotors are the same no matter the color

"Personalize the standard M Compound Brakes with red calipers. Standard M Compound brakes, regardless of color, feature ventilated brake discs, which apply aggressive braking power. The lightweight construction further improves the handling response and braking performance of your BMW."

So I'm thinking just some strange supply chain complication where reds are getting Akebono and blues are getting Pagid

[Squidget]

Holy fuckin hell I hate supply chain madness and "it's equivalent so we don't document it" policies. This thread is just making me sad.

Because it's not just going to be the original pads, anyone replacing pads later with OEM parts is gonna be playing the lottery.

Makes me want to swap to Red Stuffs simply because I know what I'll get.

I guess, for sake of argument, does anyone with blue calipers actually have lots of squeaking?

[tommycr]

Not sure if anyone posted this but I’ve seen a few videos about this on YouTube…

https://youtu.be/PYWRDNNdSp0?si=OzxfbV2togKt9-AB

[tylerdurdem]

Originally Posted by Squidget

Holy fuckin hell I hate supply chain madness and "it's equivalent so we don't document it" policies. This thread is just making me sad.

Because it's not just going to be the original pads, anyone replacing pads later with OEM parts is gonna be playing the lottery.

Makes me want to swap to Red Stuffs simply because I know what I'll get.

I guess, for sake of argument, does anyone with blue calipers actually have lots of squeaking?

Blue calipers here, wouldn't say a lot, but definitely some on light brake application at low speed. No vibration issues though after ~3300 miles.

[new2M2]

No shaking at all like the video above, but the low speed squeal is insane on mine. Red calipers. Has anyone successfully had BMW correct this issue with a non modded G87? I'm trying to find a non track place to do the 10-15 bedding procedure safely but that's all the options I see left.

[KevM2]

First a tire lottery and now a pad lotto… or should I say Russian roulette

I’m no brake expert but is it safe to assume that the brake pad compound is so soft that debris/rust/rocks easily embed themselves in it and then shave grooves on the rotors which can then cause squealing/vibration?

[CadolinaRipr]

Originally Posted by KevM2

First a tire lottery and now a pad lotto… or should I say Russian roulette

I’m no brake expert but is it safe to assume that the brake pad compound is so soft that debris/rust/rocks easily embed themselves in it and then shave grooves on the rotors which can then cause squealing/vibration?

Wonder if the rear caliper M clip has any indication ?

[KevM2]

I just hope this whole supply chain shortage crap hasn’t affected other parts of the car or more important internals… makes me wonder about that whole issue with some having problems with their knock sensors needing replacement.… a pad is easy to change as most people that track would anyways but still, it’s the principle

[baron95]

Originally Posted by KevM2

I’m no brake expert but is it safe to assume that the brake pad compound is so soft that debris/rust/rocks easily embed themselves in it and then shave grooves on the rotors which can then cause squealing/vibration?

The grooves are most often caused by the pad material itself (not foreign material). Usually if you use performance pads mostly on the street (I.e. without reaching high temps) and/or without bedding them in, the pad material transfer layer to the rotor wears off and the pad starts to etch grooves directly on the rotor surface.

Just remember that performance pads are designed to to work on contact from the pad to a pad deposition layer on the rotor surface.

You have to bed then in and periodically repes to maintain that transfer layer.

Just make it a point to get your brakes hot enough often. I know it is counter intuitive - but if you baby the brakes they will wear out faster and more unevenly.

[DSTR]

Originally Posted by tylerdurdem

Blue calipers here, wouldn't say a lot, but definitely some on light brake application at low speed. No vibration issues though after ~3300 miles.

Blue calipers. 4800kms no sound issues. No vibration issues. Dont care what pads they used. They work. Will replace with same when needed unless something changes!

[KC87ZB]

I believe from the configurator for the M2 that red and blue calipers are just a color choice with the same pad.

Previously there were upgrade options with some M cars and the different color calipers actually had different pads, similar to what Porsche used to do. I do not believe this is the case with the G8x cars at all.

Not saying there couldn’t be different pads but I don’t see where different friction expectations would exist other than a slight difference by supplier.

[apez]

Originally Posted by baron95

The grooves are most often caused by the pad material itself (not foreign material). Usually if you use performance pads mostly on the street (I.e. without reaching high temps) and/or without bedding them in, the pad material transfer layer to the rotor wears off and the pad starts to etch grooves directly on the rotor surface.

Just remember that performance pads are designed to to work on contact from the pad to a pad deposition layer on the rotor surface.

You have to bed then in and periodically repes to maintain that transfer layer.

Just make it a point to get your brakes hot enough often. I know it is counter intuitive - but if you baby the brakes they will wear out faster and more unevenly.

Any advice for bedding breaks on a new car in cold winter environment? Standard repeated 80 to 30 hard breaking sessions? Obviously on dry roads!

[baron95]

Originally Posted by apez

Any advice for bedding breaks on a new car in cold winter environment? Standard repeated 80 to 30 hard breaking sessions? Obviously on dry roads!

Air temperature will not have any meaningful impact on bedding. Stoptech has great write ups on it.

When you get a new car or put on new pads, apply brakes moderately for a several miles to get everything to match up.

When you go to do the bedding, first do ~5 ~80-40MPH applications at ~50% effort - goal here is to just warm up the pads/rotors. Drive for a minute or two to let temperatures stabilize. Then start the bedding.

For most street/track combo pads, it will take ~6-10 hard (just short of ABS) brake applications from ~80MPH to 20MPH in quick succession brake-accelerate-brake. Don't go by a set number - you you know (smell and fade) when your pads get hot enough to transfer material to the rotor. Then drive 5-10 min with no brake application to let it all cool down.

After first bedding it, if you only use the brakes on the street it is important to repeat an abbreviated version of the above every so often. I.e. periodically make your brakes get to high temps. (the only difference is that your pads will smell less and fade less or not at all second/third time around)

Hope it helps.

[aerobod]

Originally Posted by apez

Any advice for bedding breaks on a new car in cold winter environment? Standard repeated 80 to 30 hard breaking sessions? Obviously on dry roads!

The tyres will soon warm up if it is above freezing due to the repeated stops. I normally use 10-110-10km/h (6-68-6mph) repeatedly just within not activating the ABS, on a straight quiet road until the smell of the brakes is just noticeable (about a dozen stops on a high performance car if each cycle takes about 15 seconds). Then drive around for 15 mins without coming to a full stop (such as on the highway after the brake bedding).

[mynameisnick4]

Originally Posted by new2M2

No shaking at all like the video above, but the low speed squeal is insane on mine. Red calipers. Has anyone successfully had BMW correct this issue with a non modded G87? I'm trying to find a non track place to do the 10-15 bedding procedure safely but that's all the options I see left.

I have the red calipers and also have the low speed squeal. It's fairly annoying but assumed with the number of people also having it, it was 'normal' and would have to deal with it.

[baron95]

Originally Posted by aerobod

The tyres will soon warm up if it is above freezing due to the repeated stops.

Yes, there is this myth that the summer tires will have no grip if it is cold out. That is only true for the first mile or so you drive. After that, the tires will have enough heat in them to perform well in the absence of precipitation.

Just drive carefully until the tires warm up. Doing a few slow speed accelerate/brake cycles is a good way to warm them up faster.

[Ian Rogers]

It rains in the summer. I have never had issues with Summer tires in the wet. I have had issues in the cold. Get the road down to freezing temps and they do not work well.