Z4-forum.com

Hi Guys,
Newbie from Australia here, recently got a Z4M coupe and there is an issue with the rear brake caliper clips rubbing on the outside of the disc bell. (On both sides)

When I brought the car a few months ago it had what looked like newish discs and pads all round, but the clips on the rear would occasionally rub on the disc bell. I bend the clips slightly which temporarily helped but as the pads have worn it has come back as the clip goes further towards the hub where the bell has a larger diameter.

I ordered some new clips which are pictured, thinking the clips may have been wrong, but these are exactly the same.

Any ideas anyone? How much clearance does everybody else have here?

Could it be an aftermarket brake disc which is slightly the wrong shape?
Or worn sliders that are letting the caliper move around more than it should?

They must be the wrong ones. There isn't enough curve on them.

Wow, those calipers look really close to the bell to me! Normal on a Z4m?

Hi Ian, great to see another fellow Aussie Z4M enthusiast! What's the details of your car? Colour and spec?

I just had a look on my car and there is about 3mm of clearance between the rotor Bell and the clip, so something is amiss there, but there is a bigger issue here: someone has fitted the completely wrong brake pad! I don't know if it was the previous owner or a mechanic who did it but either way they're a clown for not noticing that the pad isn't even covering 20% of the rotor area! The entire rotor surface should be smooth.

So I suspect having the incorrect pad is what's allowing the clip to touch the bell.

Here's a close up of my caliper: you can see that the pad is far bigger than on yours: Go to Clickable Automotive for some replacements:
https://clickableautomotive.com.au/bmw- ... 03241.html

If you need any more local advice let me know

guess that’s why the spring is the wrong shape, as you say 5he pads are way too small and not applying the correct pressure points on the spring clip.

Thanks for the replys, that makes sense.

The old owner definitely was not a mechanic but not sure which garage did the brakes for him, I'm about to fit the 6pot BMW performance calipers to the front and was going to get new pads front and rear anyway, so will make sure I get the right ones.

The wrong pads here though is less dangerous than the wrong discs that came on a old Peugeot 206 GTI 180 I brought to turn into a trackcar, I pulled the old pads out as I was stripping and fixing things and saw the smaller discs from a normal GTI were on there so the top of the pad hangs over the top of the rotor and is unworn as the pad below is wearing down, so eventually the top of the 2 pads would have been touching and no more front brakes. Dodgy As!

Ianv wrote: ↑Mon Jan 28, 2019 1:15 am so eventually the top of the 2 pads would have been touching and no more front brakes. Dodgy As!

Whoah now that's scary!

Ianv wrote: ↑Mon Jan 28, 2019 1:15 am I'm about to fit the 6pot BMW performance calipers to the front and was going to get new pads front and rear anyway, so will make sure I get the right ones.

This is need more details on! I attempted to do the F8x front rotor and caliper upgrade on my Z4 a few weeks back under advice from the E46 M3 guys who are all doing that upgrade but alas the kingpin on the Z4M is different so it doesn't work
I'm now looking into some other options.

Mangozac wrote: ↑Mon Jan 28, 2019 10:45 am

Ianv wrote: ↑Mon Jan 28, 2019 1:15 am so eventually the top of the 2 pads would have been touching and no more front brakes. Dodgy As!

Whoah now that's scary!

Ianv wrote: ↑Mon Jan 28, 2019 1:15 am I'm about to fit the 6pot BMW performance calipers to the front and was going to get new pads front and rear anyway, so will make sure I get the right ones.

This is need more details on! I attempted to do the F8x front rotor and caliper upgrade on my Z4 a few weeks back under advice from the E46 M3 guys who are all doing that upgrade but alas the kingpin on the Z4M is different so it doesn't work
I'm now looking into some other options.

Aww I was just going to pull the trigger on a set from the f8x (facebook bmw groups - was it you? haha) in hopes of being able to fit them on mine with those kits. Sucks to hear - thanks for the info though!

Caosa wrote: ↑Tue Apr 20, 2021 12:31 am Aww I was just going to pull the trigger on a set from the f8x (facebook bmw groups - was it you? haha) in hopes of being able to fit them on mine with those kits. Sucks to hear - thanks for the info though!

In the end I just went with the E8x 135i calipers. Easiest option, and with a coat of blue metallic paint they look just as good as the F8x Brembos!