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M40i brakes - design flaw uncovered

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TheGingerOneNI
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M40i brakes - design flaw uncovered

Post by TheGingerOneNI » Thu Mar 04, 2021 8:14 pm

Jim S wrote: Wed Mar 03, 2021 10:39 pm
TheGingerOneNI wrote: Wed Mar 03, 2021 10:26 pm Is this also an issue with the Supra? If not is there a different heat shield on them?
I have not heard that the Supra has the same problem. As far as I am aware it is only BMW and Mini that is affected, as the M Sport brakes in these models all use the same design of heat shield. :driving:
Then I wonder is the heat shield in the Supra different in design and can it be fitted to the Z4? If anyone has a friend with a Supra it might be worth looking in to.

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M40i brakes - design flaw uncovered

Post by raven » Fri Mar 05, 2021 4:35 pm

Smartbear wrote: Thu Mar 04, 2021 12:15 am
Jim S wrote: Tue Jan 05, 2021 10:24 am
john-e89 wrote: Tue Jan 05, 2021 9:58 am

I was thinking of attaching it to the inside of the shield Jim, thus not making it any higher then the top of the shield, in fact a good few mm’s below the top.
Yes John, I can see that that might work but I would not want to void my warranty. BMW really should seriously consider designing a new front set of heat shields for the M Sport brakes, not only for the Z4 G29 but also for the several other series models where they are fitted. And they should retrospectively fit them to ALL affected models. I think the cost of recalling all the affected cars is what will prevent BMW from carrying this out. Shame on BMW as they are putting profits ahead of the extreme inconvenience that this is causing customers like me and several others that have been affected by this problem. :headbang:
If you modified the disc shield i don’t think it would nullify the warranty for any other part of the car apart from the shield.
If the exhaust fell off for example, it would still be covered.
Rob
if the exhaust didn't get hit by the modified brake part flying off... :rofl:
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M40i brakes - design flaw uncovered

Post by raven » Fri Mar 05, 2021 4:40 pm

TheGingerOneNI wrote: Thu Mar 04, 2021 8:14 pm
Jim S wrote: Wed Mar 03, 2021 10:39 pm
TheGingerOneNI wrote: Wed Mar 03, 2021 10:26 pm Is this also an issue with the Supra? If not is there a different heat shield on them?
I have not heard that the Supra has the same problem. As far as I am aware it is only BMW and Mini that is affected, as the M Sport brakes in these models all use the same design of heat shield. :driving:
Then I wonder is the heat shield in the Supra different in design and can it be fitted to the Z4? If anyone has a friend with a Supra it might be worth looking in to.
The supra brakes look identical to me:
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I doubt there are many parts actually designed by Toyota on the Supra :-)
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M40i brakes - design flaw uncovered

Post by ronk » Fri Mar 05, 2021 5:17 pm

The backplates don’t look the same?
That’s where the problem starts I think.
Last edited by ronk on Fri Mar 05, 2021 11:14 pm, edited 1 time in total.
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M40i brakes - design flaw uncovered

Post by Argyll Andy » Fri Mar 05, 2021 6:11 pm

Not conclusive as in the pictures they look different and the Supra lip looks to curve over the top of the discs whereas the G29 looks to taper out the way which I presume allows the stones in and become trapped.

What looks like the better news is on the OE website for both cars the plates looks the same, same pattern, mounting points etc so if the above is correct will possibly offer protection the BMW one doesn’t. So what we need is an M40i owner who has the time and inclination to order one (or take the punt it’s different and buy a pair) and compare them and do a like for like. If ok and they want keep and fit, if not return for a refund??
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    M40i brakes - design flaw uncovered

    Post by raven » Sat Mar 06, 2021 8:41 am

    ronk wrote: Fri Mar 05, 2021 5:17 pm The backplates don’t look the same?
    That’s where the problem starts I think.
    Maybe, I can not find any good pictures showing the backplates :(
    In the diagrams look pretty much the same to me, I doubt they will be different :)
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    M40i brakes - design flaw uncovered

    Post by Jim S » Sat Mar 06, 2021 12:40 pm

    You need to compare them looking at a front view.
    896B80E3-F43C-404E-A06F-85B1C859E123.jpeg
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    M40i brakes - design flaw uncovered

    Post by ronk » Sat Mar 06, 2021 12:46 pm

    That’s an open invite for stones and debris !
    Good for airflow but nothing else.

    The bottom of the backplate looks like a good way of preventing a stone dropping out :thumbsdown:
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    M40i brakes - design flaw uncovered

    Post by Argyll Andy » Sat Mar 06, 2021 5:26 pm

    Jim S wrote: Sat Mar 06, 2021 12:40 pm You need to compare them looking at a front view.
    896B80E3-F43C-404E-A06F-85B1C859E123.jpeg
    That is a shocking gap Jim, the stones can only go one way - in :thumbsdown:

    I wonder if there a Supra forum to see if there’s any similar complaints or comparison pictures :lol:

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      M40i brakes - design flaw uncovered

      Post by Jim S » Sat Mar 06, 2021 7:26 pm

      Argyll Andy wrote: Sat Mar 06, 2021 5:26 pm
      Jim S wrote: Sat Mar 06, 2021 12:40 pm You need to compare them looking at a front view.
      896B80E3-F43C-404E-A06F-85B1C859E123.jpeg
      That is a shocking gap Jim, the stones can only go one way - in :thumbsdown:
      And they get trapped at the bottom because the heat shield turns in at the track rod end closing the gap. :headbang:

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      M40i brakes - design flaw uncovered

      Post by Argyll Andy » Sat Mar 06, 2021 7:32 pm

      Jim S wrote: Sat Mar 06, 2021 7:26 pm
      Argyll Andy wrote: Sat Mar 06, 2021 5:26 pm
      Jim S wrote: Sat Mar 06, 2021 12:40 pm You need to compare them looking at a front view.
      896B80E3-F43C-404E-A06F-85B1C859E123.jpeg
      That is a shocking gap Jim, the stones can only go one way - in :thumbsdown:
      And they get trapped at the bottom because the heat shield turns in at the track rod end closing the gap. :headbang:
      Be better not having them than that backwards design :thumbsdown:

      Stupid question maybe but are they actually necessary?

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        M40i brakes - design flaw uncovered

        Post by Jim S » Sat Mar 06, 2021 7:53 pm

        I asked my dealer if I could have the heat shields removed as they are not really necessary unless you are on the race track or driving the car very hard, causing the disks to really heat up. The dealer was not too keen to remove them. :thumbsdown:
        However, I told the dealer that if I keep getting stones trapped in the brakes that I might insist on having the shields removed. So far I have not reached that point yet, but I won’t discount that option in the future. :headbang:

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        M40i brakes - design flaw uncovered

        Post by ronk » Sat Mar 06, 2021 8:03 pm

        Jim S wrote: Sat Mar 06, 2021 7:53 pm I asked my dealer if I could have the heat shields removed as they are not really necessary unless you are on the race track or driving the car very hard, causing the disks to really heat up. The dealer was not too keen to remove them. :thumbsdown:
        However, I told the dealer that if I keep getting stones trapped in the brakes that I might insist on having the shields removed. So far I have not reached that point yet, but I won’t discount that option in the future. :headbang:
        I think I would be more tempted to go into a Toyota dealership and discuss your options with them ?

        If the Toyota part is fitted and the stone trap problem goes away, you’ll have a big stick to hit them with!
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        M40i brakes - design flaw uncovered

        Post by Jim S » Sat Mar 06, 2021 8:06 pm

        ronk wrote: Sat Mar 06, 2021 8:03 pm
        Jim S wrote: Sat Mar 06, 2021 7:53 pm I asked my dealer if I could have the heat shields removed as they are not really necessary unless you are on the race track or driving the car very hard, causing the disks to really heat up. The dealer was not too keen to remove them. :thumbsdown:
        However, I told the dealer that if I keep getting stones trapped in the brakes that I might insist on having the shields removed. So far I have not reached that point yet, but I won’t discount that option in the future. :headbang:
        I think I would be more tempted to go into a Toyota dealership and discuss your options with them ?
        I would want the work done under warranty. :driving:

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        M40i brakes - design flaw uncovered

        Post by ronk » Sat Mar 06, 2021 8:14 pm

        Jim S wrote: Sat Mar 06, 2021 8:06 pm
        ronk wrote: Sat Mar 06, 2021 8:03 pm
        Jim S wrote: Sat Mar 06, 2021 7:53 pm I asked my dealer if I could have the heat shields removed as they are not really necessary unless you are on the race track or driving the car very hard, causing the disks to really heat up. The dealer was not too keen to remove them. :thumbsdown:
        However, I told the dealer that if I keep getting stones trapped in the brakes that I might insist on having the shields removed. So far I have not reached that point yet, but I won’t discount that option in the future. :headbang:
        I think I would be more tempted to go into a Toyota dealership and discuss your options with them ?
        I would want the work done under warranty. :driving:
        Then think you are going to have to start banging the table.
        There is an area visiting BMW tech guru - I suggest you ask for a meeting with him . I had a problem with my car albeit minor, he sanctioned a very agreeable compensation package.
        You don't stop playing when you get old - You get old when you stop playing!
        So I bought a 35is with all the toys to play with. :thumbsup:

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