[Artemis]

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CFRP (Carbon Fiber Reinforced Polymer) weave patterns: see for example here ("Carbon Fiber - All Patterns Explained").

CFRP roof - smaller sized weave pattern: for example BMW M4 Edition M Heritage (F82):


CFRP roof - bigger sized weave pattern ('checker/chess board' look): for example BMW M2 CS (F87):


The 'shark fin' on BMW M CFRP roofs is gloss black (a CFRP housing would be less optimal for the antenna signal).

The BMW M2 CS features a new type of CFRP roof:

"The new roof, with its sandwich design, makes the body more rigid and appears to have been cut from the same mould as the rest of the car; no trim strips are needed, meaning no visible join[t]s either. This has the additional effect of enhancing acoustics, both inside and outside the car. And dispensing with the customary roof bows and insulation also saves weight. Together with the lighter bonnet, this serves to lower the vehicle’s centre of gravity, resulting in even better driving dynamics."
(source: BMW press materials - see here)

A couple of peculiarities about the BMW M2 CS roof:

• only available on the BMW M2 CS;
• sandwich-structured composite for improved rigidity, structurally integrated;
• no roof rack anchorage points (roof drip rail with flaps);
• bigger sized weave pattern ('checker/chess board' look), unlike all other BMW M2 CS CFRP parts (smaller sized weave pattern) (no size uniformity, which in itself is a peculiar design choice).

Now here's the problem. It appears that CFRP roofs of several BMW M2 CS cars feature sections with irregular weave patterns (see pictures below).

Rather puzzling how this sloppy look made it through BMW M quality control.

A Bimmerpost forum member heard through the grapevine more about this aesthetic issue and, unfortunately, it sounds a little embarrassing:

Originally Posted by MR.

With regards to the roof, I can say the following that it is major "f*** up" by BMW M. I got info about the roof from an insider and what I heard was like #triplefacepalm

Just to summarize the final outcome... The roof is painted and tinted to disguise errors you can see from a distance. They do this three or four times and sand it down by hand after every layer of clear coat just to make sure you don't notice it.

Yep, let that sink in... The roof was not meant to be like this and everyone knows it in Garching.

Originally Posted by MR.

Yep, this improved rigidity and was a better option according [to] them, but clearly they did not explain the whole story. With the additional information I can confirm no other M car will have this roof. Nobody wants to take the risk of dealing with a fail again.

Nothing more than that the solution for those problems came too late to homologate the car and have it in time ready for market release. Europe would have missed out too much on the CS due to the production stop in September.

They are partly hand made to deal with the irregularity. The production process was initially wrong, but the fix came too late. So all the cars I have seen so far have the problem in the roof, simply because the fix could not be introduced anymore in time. Now it needs handwork to deal with it. They tint it to give you the idea it is so bad. #facepalm

The aesthetic issue was also pointed out in this video (see 05:39 to 06:54).

Examples on BMW M2 CS cars (demo cars as well as production/delivered cars):






















(picture sources: here, here, here, here, here and here)

The aesthetic issue was already noticed on the BMW M2 CS press car on display in Los Angeles (Autumn 2019):

Originally Posted by MinionM3

All these posts from the autoshow and nobody noticed the imperfection in the roof weave!?!?! If this was my car from factory I'd be furious!

Hope the production models don't have this....

A BMW M2 CS owner approached the aesthetic issue with a positive twist:

Originally Posted by Turbomeister

Same spec here, I agree on the roof not being perfect, but all those imperfections are unique ! No car is the same as the other !

For the record: BMW M2 CS test car in Summer 2019 revealing ...a smaller sized weave CFRP roof (or a wrap):

(source: here)

M Performance Parts CFRP roof for the original BMW M2 and the BMW M2 Competition (BMW part # 41 31 2 460 277): smaller sized weave pattern:

(source: here)

[medphysdave]

If my M2CS has any roof defects I'll certainly have a conversation with BMW USA. We don't really have the option to have another car built, or have the roof replaced. Hopefully no one is seeing this on the non press cars.

[gemini.m3]

Originally Posted by medphysdave

If my M2CS has any roof defects I'll certainly have a conversation with BMW USA. We don't really have the option to have another car built, or have the roof replaced. Hopefully no one is seeing this on the non press cars.

Looks like Turbomeister has it- hopefully they got it better as production went on

You could look at it two ways, I’d prefer glass half full and that if this ends up being the only bmw with this pattern- pretty rare, defects and all

On the flip side not real acceptable IMO. Seems like with covid halting production they really pushed these cars out ASAP.

[Hedoniste]

I didn't see any problem on the CS I bought but it was raining. I will pick up the car on Wednesday and I hope to be quickly able to inspect the roof under direct sunlight. I will post here asap my feedback. Thanks for creating this thread

[medphysdave]

I liken this to a run in the paint. Each roof is like a snowflake . You don't get a numbered car, just a unique defect.

[F87EVO]

My guess is that every M2 CS has those imperfections , but not at the same places. Of course its not a deal braker , and it would rather be perfect than "unique" , but now its over , just take that approach , it was first tested on the M2 CS , each car/roof is unique with those small imperfections. Coming from the OG M2 , i love the CFRP roof , looks like a racing flag ! 🏁 by the way , those imperfections are so minimal in reality , and i also have to admit that the 1x1 weave on the M2 CS is much better looking than the 2x2 . I will provide more photos of the roof tomorrow.

[Supadice]

Originally Posted by Turbomeister

My guess is that every M2 CS has those imperfections , but not at the same places. Of course its not a deal braker , and it would rather be perfect than now , but now its over , just take that approach , it was first tested on the M2 CS , each car/roof is unique with those small imperfections. Coming from the OG M2 , i love the CFRP roof , looks like a racing flag ! 🏁 by the way , those imperfections are so minimal in reality , and i also have to admit that the 1x1 weave on the M2 CS is much better looking than the 2x2 . I will provide more photos of the roof tomorrow.

Your roof looks pretty good

[VisualEcho]

As long as it doesn't crack or peel like the older ones.

[F87EVO]

Originally Posted by Supadice

Your roof looks pretty good

It has some imperfections but not huge deal ..some roofs look "better" and some other look "worse" . But again , not a big deal , yes for the money it may be unacceptable , but "unique" at the same time.

At least looks like a real CF roof , not just a CF wrap !

Looks handmade too - maybe is ?!

[F87EVO]

Originally Posted by VisualEcho

As long as it doesn't crack or peel like the older ones.

That would be an issue ! Buuuut , for real now it seems too strong for that case. It feels too , i ve sat on the roof

[sdhotwn]

my wife and I were discussing this last night and she said that if it was really bad I should put a CF vinyl wrap on it, "It's not fake, because it really is CF under" LOL

[Artemis]

Originally Posted by VisualEcho

As long as it doesn't crack or peel like the older ones.

This one on a 2015 F80 M3 didn't age well:

Originally Posted by dd1eye

This is what my 2015 M3's carbon fiber roof looks like. It started peeling at around the 3.5 year mark. I have taken it to multiple BMW service centers but BMW refuses to fix it even though it was under warranty. They say the reason for the peeling is rocks hitting the car even thought it is peeling in the middle and the back of the roof. For the first 3 years I drove the same road and if there rocks hitting the roof why didn't it start peeling sooner.



Has anyone had similar issues with the CB roof?

[VisualEcho]

Originally Posted by Artemis

This one on a 2015 F80 M3 didn't age well:

Dude, I would be so sick if that happened to me. It's enough to make me stay away from CF roofs altogether.

But if I'm honest, I'm just mad they didn't make it forged carbon fiber. They could have toned it down a bit and it would have looked (and performed) awesome.

[ASAP]

I would say for the price this is unacceptable... but seeing how this is a new weave, it doesn't surprise me... what would get me are cracks... a friends F80 started developing cracks after 4 years... FYI - no one can fix CF correctly... and how do you replace it?

[BimR]

Originally Posted by Artemis

This one on a 2015 F80 M3 didn't age well:

This is horrible! The small imperfections are annoying but unless I'm misunderstanding, this is peeling badly.

[JustChris]

Not good, I wish owners well in resolving if they have issues.....but I will say this.

Fair play to Bimmerpost for not hiding this and making it front page.

[01'325rip]

Originally Posted by VisualEcho

Dude, I would be so sick if that happened to me. It's enough to make me stay away from CF roofs altogether.

But if I'm honest, I'm just mad they didn't make it forged carbon fiber. They could have toned it down a bit and it would have looked (and performed) awesome.

As cool as this would be, forged carbon would not work on the roof. You need something with more structural integrity. Forged carbon is more for aesthetic pieces because it lacks in strength vs twill and directional weave.

[gds52]

BMW hired Tesla workers

[1bmwaddict]

Thats why you dont buy the first batch!

[frankiebones]

Originally Posted by Turbomeister

My guess is that every M2 CS has those imperfections , but not at the same places. Of course its not a deal braker , and it would rather be perfect than "unique" , but now its over , just take that approach , it was first tested on the M2 CS , each car/roof is unique with those small imperfections. Coming from the OG M2 , i love the CFRP roof , looks like a racing flag ! by the way , those imperfections are so minimal in reality , and i also have to admit that the 1x1 weave on the M2 CS is much better looking than the 2x2 . I will provide more photos of the roof tomorrow.
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The color of the roof is stunning and looks lighter than a normal CF roof. I am correct?

[Luminor513]

Some of these look like they could be some kind of environmental damage, maybe prolonged exposure to something?

[biggripper]

Originally Posted by Artemis

This one on a 2015 F80 M3 didn't age well:

This is part of the reason that I covered my entire roof in Xpel on my '16 M4 when I sold the car in 2019 it still looked perfect.