[Sebastian212az]

So I was driving my M2 competition in the local canyons near my house and about 30 minutes in my brakes started to fade so I chilled out a little but about 5-10 minuets later it got really bad to the point where i was pressing the brakes very hard and the car was barely stopping I had to pull over and wait a little long
till It was safe enough to drive home, anyone know why this happened?
lol

[chris719]

Should not happen on the street. May be a pad or fluid issue? Seems weird.

[hellrotm]

I had similar issues with my M4 during long periods of hard driving. Until I changed pads and fluid, I had to do cool down periods to prevent fade. See if the new Mperf pads are available. If you weren’t driving that hard, you could have air in your lines.

[hellrotm]

Originally Posted by chris719

Should not happen on the street. May be a pad or fluid issue? Seems weird.

SoCal canyons are not your typical streets. You can heat up brakes quicker in the canyons than most tracks.

[KillBill999]

E92 M3 has same issues....unfortunately it seems if you track your M, you will need a big brake kit or an aftermarket rotor with upgraded pads...sux.

[Gearhead999s]

Originally Posted by Sebastian212az

So I was driving my m2 competition in the local canyons near my house and about 30 minutes in my brakes started to fade so I chilled out a little but about 5-10 minuets later it got really bad to the point where i was pressing the brakes very hard and the car was barely stopping I had to pull over and wait a little long
till It was safe enough to drive home, anyone know why this happened?
lol

I gather you did not bed in your brakes first.Green Fade will happen with new pads if you do not do a pad break in which means getting the pAds hot enough to boil the bonding agents out of the pads and then let them cool down before using them hard again.

[gnx]

Originally Posted by KillBill999

E92 M3 has same issues....unfortunately it seems if you track your M, you will need a big brake kit or an aftermarket rotor with upgraded pads...sux.

What could the marginal benefit be of a BBK compared to the 2NH big brake kit manufctured by Brembo?

[Apachesmith]

So this is the second thread referring to significant brake fade. Do we think there has been a bad batch of brakes produced by Brembo and these are some from that batch (current delivery delays on the larger brakes which may be linked to a "bad batch" issue) or more unlikely a design fault? I would be interested if anyone else on the forum has noticed brake fade on hard driving - If so this may be a more systemic issue rather than a bad batch?

OP, I would take the car back to the dealership and ask them to look if there are any issue with the brake fluid (air in it) as you shouldn't see brake fade on a car of this performance level on regular roads unless you really were really hammering it.

No reports from Ascari where the ambient temperatures were in the mid - high 30's (celsius) and they were getting hammered lap after lap by multiple journalists - either its a batch issue or BMW "upgraded" the fluids and pads for the test cars, which would be disappointing at best!

[ChrisK]

Originally Posted by Apachesmith

So this is the second thread referring to significant brake fade. Do we think there has been a bad batch of brakes produced by Brembo and these are some from that batch (current delivery delays on the larger brakes which may be linked to a "bad batch" issue) or more unlikely a design fault? I would be interested if anyone else on the forum has noticed brake fade on hard driving - If so this may be a more systemic issue rather than a bad batch?

OP, I would take the car back to the dealership and ask them to look if there are any issue with the brake fluid (air in it) as you shouldn't see brake fade on a car of this performance level on regular roads unless you really were really hammering it.

No reports from Ascari where the ambient temperatures were in the mid - high 30's (celsius) and they were getting hammered lap after lap by multiple journalists - either its a batch issue or BMW "upgraded" the fluids and pads for the test cars, which would be disappointing at best!

When BMW did the original track event for the M2, the pads were track pads. You can hear them squealing in the videos.

There has been varying opinions on the pads at Ascari. One person said yes, another said no to track pads being on the cars. After watching as many videos as possible, I never heard the infamous track pad squeal. :

I have no idea.

[F87_LCI]

Originally Posted by Apachesmith

No reports from Ascari where the ambient temperatures were in the mid - high 30's (celsius) and they were getting hammered lap after lap by multiple journalists - either its a batch issue or BMW "upgraded" the fluids and pads for the test cars, which would be disappointing at best!

Possible said "journalists" simply wanted to ensure they are continued to be invited to these events, so they don't report anything significantly negative about the cars they "test"?? In my books this would be a significant issue for a car that is designed to pull double duty as road/track car. Guess we'll have to wait and see if any more owners experience the issue.

[carl44]

The brakes are plenty big. 400 mm my gt4 is 380with 6+4 piston calipers same as the M2C.
Could only be four things or a combination of them.
1) pads
2)fluid
3) cooling
4)to small of a master cyclinder for the larger calipers.

Don't know how you could make a defective set of brakes as stated earlier . They are very simple if they don't leak there ok. Carl

[3tekcorps]

Originally Posted by hellrotm

SoCal canyons are not your typical streets. You can heat up brakes quicker in the canyons than most tracks.

Really?.. Which canyons and tracks specifically?

[pal]

OP, did the pedal go to the floor (boiled fluid) or was the pedal stiff but not enough braking (pad fade)? If the former, then all you likely need is a good flush with some RBF (Castrol SRF, Motul RBF 660, Brembo LCF 600+ or equivalent) and you’d be good to go.

[cptobvious]

Originally Posted by Apachesmith

So this is the second thread referring to significant brake fade. Do we think there has been a bad batch of brakes produced by Brembo and these are some from that batch (current delivery delays on the larger brakes which may be linked to a "bad batch" issue) or more unlikely a design fault? I would be interested if anyone else on the forum has noticed brake fade on hard driving - If so this may be a more systemic issue rather than a bad batch?

OP, I would take the car back to the dealership and ask them to look if there are any issue with the brake fluid (air in it) as you shouldn't see brake fade on a car of this performance level on regular roads unless you really were really hammering it.

No reports from Ascari where the ambient temperatures were in the mid - high 30's (celsius) and they were getting hammered lap after lap by multiple journalists - either its a batch issue or BMW "upgraded" the fluids and pads for the test cars, which would be disappointing at best!

Hey guys, I think Apachesmith is right here. If there's an issue, it would fall into 1 of 3 buckets:

1. Individual defect
2. Batch issue
3. Systemic issue

I'm making a wild conjecture here, but if I had to put money on a wager at this time, I would guess it's #2.

Here's my reasoning:

a) We've heard this issue from more than 1 member now, so it's probably not #1
b) But, it's probably not #3, because I haven't experienced any braking issues at all to-date. In fact, for me, the brakes have been awesome, and I've been hammering them as hard as I can for 1,200 miles now
c) All 1,200 miles have been put in on mountain and canyon roads in SoCal (Mt. Palomar Observatory over to Julian down to Lake Cuyamaca, over to Otay Lakes, then to Campo). If any of you are familiar with those routes, they're steep and windy and they're typically motorcycle heaven, so lots and lots of braking involved
d) Now, granted, maybe I'm not hitting the brakes hard enough, but on a couple of occasions now, the switchback / mountainous portion of the route I've done has been ~100 miles in total length, so I would imagine that the route is giving the brakes enough of a real workout

I hope we get to the bottom of this issue!

[chris719]

Originally Posted by carl44

The brakes are plenty big. 400 mm my gt4 is 380with 6+4 piston calipers same as the M2C.
Could only be four things or a combination of them.
1) pads
2)fluid
3) cooling
4)to small of a master cyclinder for the larger calipers.

Don't know how you could make a defective set of brakes as stated earlier . They are very simple if they don't leak there ok. Carl

It's not 4, the CCB option with gold calipers use the same master cylinder. That wouldn't cause fade either, just a consistently bad pedal feel.

[3tekcorps]

Originally Posted by cptobvious

Hey guys, I think Apachesmith is right here. If there's an issue, it would fall into 1 of 3 buckets:

1. Individual defect
2. Batch issue
3. Systemic issue

I'm making a wild conjecture here, but if I had to put money on a wager at this time, I would guess it's #2.

Here's my reasoning:

a) We've heard this issue from more than 1 member now, so it's probably not #1
b) But, it's probably not #3, because I haven't experienced any braking issues at all to-date. In fact, for me, the brakes have been awesome, and I've been hammering them as hard as I can for 1,200 miles now
c) All 1,200 miles have been put in on mountain and canyon roads in SoCal (Mt. Palomar Observatory over to Julian down to Lake Cuyamaca, over to Otay Lakes, then to Campo). If any of you are familiar with those routes, they're steep and windy and they're typically motorcycle heaven, so lots and lots of braking involved
d) Now, granted, maybe I'm not hitting the brakes hard enough, but on a couple of occasions now, the switchback / mountainous portion of the route I've done has been ~100 miles in total length, so I would imagine that the route is giving the brakes enough of a real workout

I hope we get to the bottom of this issue!

What we're missing is any type of testing consistency or credibility of evaluators. Not to say they're making it up, but at this point when I read someone claiming streets being a reasonable evaluator I really have to question their opinion. Have they ever down a track day and pushed a car to 100% for 30 minutes?

From my experience driving fast on the street is maybe 40% of the load you'd see in an intermediate DE group.

[M-Pilot]

Brakes shouldn't fade after a 30min canyon run unless you are driving it the way you do on a track (which is not the case most of the time with canyon driving). It doesn't sound normal to me and there is apparently something going on since this has been mentioned before as well. However, another factor is the use of MDM or full DSC on. OP, were you using any of these mods or was the DSC fully off? US spec BMWs tend to have very aggressive MDM and DSC calibration which eats up brakes easily when you try to push the car. In my opinion, most likely this has something to do with the stock pads. I would switch to a more aggresive compund pads to make a comparison and see if they still fade.

[hellrotm]

Originally Posted by 3tekcorps

Really?.. Which canyons and tracks specifically?

Malibu canyons, not going to blowup my spots. A couple roads I been driving for over decade are treacherous(cars and motorcycles). My two favorite canyon roads have those brake runoff gravel pits at the end off them. Imagine doing a 15-20min track sessions where the entire second half of session is on a steep downhill grade. It can put a hurtin on any brake system. My buddy use to roast his .1 C2 brakes.

[hellrotm]

Originally Posted by cptobvious

Hey guys, I think Apachesmith is right here. If there's an issue, it would fall into 1 of 3 buckets:

1. Individual defect
2. Batch issue
3. Systemic issue

I'm making a wild conjecture here, but if I had to put money on a wager at this time, I would guess it's #2.

Here's my reasoning:

a) We've heard this issue from more than 1 member now, so it's probably not #1
b) But, it's probably not #3, because I haven't experienced any braking issues at all to-date. In fact, for me, the brakes have been awesome, and I've been hammering them as hard as I can for 1,200 miles now
c) All 1,200 miles have been put in on mountain and canyon roads in SoCal (Mt. Palomar Observatory over to Julian down to Lake Cuyamaca, over to Otay Lakes, then to Campo). If any of you are familiar with those routes, they're steep and windy and they're typically motorcycle heaven, so lots and lots of braking involved
d) Now, granted, maybe I'm not hitting the brakes hard enough, but on a couple of occasions now, the switchback / mountainous portion of the route I've done has been ~100 miles in total length, so I would imagine that the route is giving the brakes enough of a real workout

I hope we get to the bottom of this issue!

X3 models from 18-19 currently have a recall for rear brakes having air in the lines. A sure way off creating brake fade. So certainly wouldn’t be the first time something like this happen to a batch of cars. Of all the reviews of the M2C, I remember a couple mention a soft brake pedal after track laps, but not to the extent that the OP is describing. So I would tend to lean towards a hardware issue. Remember these brakes are being sold as a Mperf upgrade as well, so they are definitely thoroughly tested.

[MadViper]

Originally Posted by Sebastian212az

So I was driving my m2 competition in the local canyons near my house and about 30 minutes in my brakes started to fade so I chilled out a little but about 5-10 minuets later it got really bad to the point where i was pressing the brakes very hard and the car was barely stopping I had to pull over and wait a little long
till It was safe enough to drive home, anyone know why this happened?
lol

Welcome to the club Sebastian. The best piece of information I read on this thread is pal comment on the difference between boiled fluid and pad fade.
On a side note. I was in the phone and emails with Pagid and Hawk and they say they dont have brake pads for the M2C yet, hard to believe.

[chris719]

Originally Posted by MadViper

Welcome to the club Sebastian. The best piece of information I read on this thread is pal comment on the difference between boiled fluid and pad fade.
On a side note. I was in the phone and emails with Pagid and Hawk and they say they dont have brake pads for the M2C yet, hard to believe.

That sucks, are the M Performance "sport" pads available?

[Sebastian212az]

Originally Posted by chris719

That sucks, are the M Performance "sport" pads available?

Not sure