Brake discs

[Smartbear]

If you are fitting them your self you could spray the new disc just on the area you mention with silver spray (be sure you mask all other surfaces) this then will keep its appearance looking good. I did this 3 years ago when I fitted new discs and they still look good today.

Apparently, manufacturers leave the hubs bare to maximise heat dispersal.

Call me a cynic but i suspect it’s cost related :?
Rob

 

[Busterboo]

I don't know, Rob. The hubs are certainly great lumps of iron.

That said, I don't like it when they go rusty.

 

[Smartbear]

I don't know, Rob. The hubs are certainly great lumps of iron.

That said, I don't like it when they go rusty.

Agreed, I’ve painted mine as they’re so unsightly when they corrode.
I suppose the wheel acts as a heat sink for hot brakes as well, I’m glad they decided to paint those
Rob

 

[YDB]

Wow Silverstar, nice clean brakes, does the car get out of the garage?

 

[Silverstar]

Wow Silverstar, nice clean brakes, does the car get out of the garage?

Yes I use it daily, just had them painted couple of weeks back so still clean! The car's going for a full detail & ceramic coating and they are going to coat the callipers as well so hopefully I can keep them that way.

 

[YDB]

Wow Silverstar, nice clean brakes, does the car get out of the garage?

Yes I use it daily, just had them painted couple of weeks back so still clean! The car's going for a full detail & ceramic coating and they are going to coat the callipers as well so hopefully I can keep them that way.

Thats a relief, I was wondering how you keep them so clean. They look good.

 

[Baza]

New discs fitted and painted callipers still look good 3 years on painting kept the rust away

 

[Busterboo]

Baza, it's not the (in your case, red) calipers I was asking about, but the (grey) hubs of the brake discs themselves.

However, your post's made me realise that on my new OE discs, it's only the rear hubs that are rusting.

Do BMW, then, leave the rear hubs bare metal because it's the larger rear discs & hubs that need to disperse heat more than the smaller front?

 

[srhutch]

Baza, it's not the (in your case, red) calipers I was asking about, but the (grey) hubs of the brake discs themselves.

However, your post's made me realise that on my new OE discs, it's only the rear hubs that are rusting.

Do BMW, then, leave the rear hubs bare metal because it's the larger rear discs & hubs that need to disperse heat more than the smaller front?

70% of the breaking is on the front, that’s where the heat will be. As said before cost will be why they don’t do it.

 

[flybobbie]

Baza, it's not the (in your case, red) calipers I was asking about, but the (grey) hubs of the brake discs themselves.

However, your post's made me realise that on my new OE discs, it's only the rear hubs that are rusting.

Do BMW, then, leave the rear hubs bare metal because it's the larger rear discs & hubs that need to disperse heat more than the smaller front?

70% of the breaking is on the front, that’s where the heat will be. As said before cost will be why they don’t do it.

Strange because my rear pads seem to wear a lot quicker than the fronts.
Perhaps the E-brake has something to do with that.

 

[Busterboo]

Baza, it's not the (in your case, red) calipers I was asking about, but the (grey) hubs of the brake discs themselves.

However, your post's made me realise that on my new OE discs, it's only the rear hubs that are rusting.

Do BMW, then, leave the rear hubs bare metal because it's the larger rear discs & hubs that need to disperse heat more than the smaller front?

70% of the breaking is on the front, that’s where the heat will be. As said before cost will be why they don’t do it.

If cost were the issue, they wouldn't paint either front or rear hubs.

 

[Busterboo]

Perhaps the E-brake has something to do with that.

Now there's a thought.

 

[Chippie]

Baza, it's not the (in your case, red) calipers I was asking about, but the (grey) hubs of the brake discs themselves.

However, your post's made me realise that on my new OE discs, it's only the rear hubs that are rusting.

Do BMW, then, leave the rear hubs bare metal because it's the larger rear discs & hubs that need to disperse heat more than the smaller front?

70% of the breaking is on the front, that’s where the heat will be. As said before cost will be why they don’t do it.

Strange because my rear pads seem to wear a lot quicker than the fronts.
Perhaps the E-brake has something to do with that.

Could the traction control applying the rear brakes limiting wheel spin ( limited slip diff ) be responsible for the rear brakes brakes wearing quicker?
And aren’t they front hubs an alloy riveted to the discs?

 

[flybobbie]

Also seeing a lot less wear and brake dust using EBC green stuff and slotted/drilled discs.

 

[Baza]

However, your post's made me realise that on my new OE discs, it's only the rear hubs that are rusting.

Do BMW, then, leave the rear hubs bare metal because it's the larger rear discs & hubs that need to disperse heat more than the smaller front?

I replaced Both front and rear discs in both cases 300mm rear 330mm front the discs came painted in silver as standard,what you see in the picture is how they came. I just added another coat for extra protection The discs were to OEM standard manufactured by ATE and supplied by Euro car parts As you don't mention your Z4 Model they may be different sizes to mine.

 

[Baza]

Woops sorry Rear was by Pagid But still painted.

 

[Silverstar]

Baza, it's not the (in your case, red) calipers I was asking about, but the (grey) hubs of the brake discs themselves.

However, your post's made me realise that on my new OE discs, it's only the rear hubs that are rusting.

Do BMW, then, leave the rear hubs bare metal because it's the larger rear discs & hubs that need to disperse heat more than the smaller front?

70% of the breaking is on the front, that’s where the heat will be. As said before cost will be why they don’t do it.

Strange because my rear pads seem to wear a lot quicker than the fronts.
Perhaps the E-brake has something to do with that.

Looking at the old invoices supplied by the previous owners he's had the rear breaks done but not the front. This Z4 is the first car I have ever come across where the rear pads go before the fronts because usually as srhutch says the front goes before the rears. Like you say maybe something to do with the E-brakes or something.

 

[enuff_zed]

70% of the breaking is on the front, that’s where the heat will be. As said before cost will be why they don’t do it.

Strange because my rear pads seem to wear a lot quicker than the fronts.
Perhaps the E-brake has something to do with that.

Could the traction control applying the rear brakes limiting wheel spin ( limited slip diff ) be responsible for the rear brakes brakes wearing quicker?
And aren’t they front hubs an alloy riveted to the discs?

Slightly stretching the topic I guess, but when I first got my E89 I drove it with everything left switched on and I was forever cleaning brake dust off the rear wheels, much more than the front in normal driving conditions.
Now I'm used to the car I switch off the traction control on most occasions and I have noticed a significant reduction in the amount of rear brake dust build up.
So there could well be truth in what you say about the rear pads wearing more quickly.

 

[Busterboo]

I replaced Both front and rear discs in both cases 300mm rear 330mm front the discs came painted in silver as standard,what you see in the picture is how they came. I just added another coat for extra protection The discs were to OEM standard manufactured by ATE and supplied by Euro car parts As you don't mention your Z4 Model they may be different sizes to mine.

I got it back to front, quite literally. My fronts are 330, of course, and rears 300. I got the paint bit right, though. My fronts came painted, the rears not.

As for dust, the fronts are heavy with it in less than a couple of hundred miles.

 

[Baza]

For less dust try ceramic brake pads