BRAKE ISSUE WITH 135i CALIPERS

[larryn]

Complete parts list and links can be found here: http://www.1addicts.com/forums/showthread.php?t=441050

There are three different sized pistons on the calipers.

[uberschnell]

Originally Posted by BiscottiGelato

Hence I don't get why there's all these calls for upgrading brakes/pads, etc for the track. Shouldn't brake cooling be the first mod above all else? Yet there seems to be so few solutions for our BMWs on this...

I tracked an e90 335 with BBK's for years and had absolutely no problems. Cooling on the 335 is no better then on the 135.

I've got a set of Brembo GT's on the front now and the brakes work flawlessly.

The stock set up is just more susceptible to heat. Thin disk plus smaller diameter are major contributors.

[JB135MDCT]

Originally Posted by MteK

I tracked an e90 335 with BBK's for years and had absolutely no problems. Cooling on the 335 is no better then on the 135.

I've got a set of Brembo GT's on the front now and the brakes work flawlessly.

The stock set up is just more susceptible to heat. Thin disk plus smaller diameter are major contributors.

Do the BBK have heat/dust shields? Maybe we can just rip them out.

[Groundpilot]

Do not remove brake dust shields. They protect wheel bearings from excessive heat.

[Focusedintntions]

Originally Posted by M3 09 AND135I 11

Do not remove brake dust shields. They protect wheel bearings from excessive heat.

This makes no sense to me....the wheels bearings are directly inward of the rotor where the dust shield doesn't block a thing....it's just there to keep debris from getting on the rotor and into the pads...

[uberschnell]

Originally Posted by JB135MDCT

Do the BBK have heat/dust shields? Maybe we can just rip them out.

I run with my dust shields. They have a nice open area at the base of the shield for air to get in.The brembo rotors also have nice air gaps between the hub and the rotor rings to draw air in.


BTW, my stock calipers looked absolutely perfect when I removed them at 45K, but they had never been to the track. I think this is a track related issue only.

[Xaeryan]

Originally Posted by MteK

BTW, my stock calipers looked absolutely perfect when I removed them at 45K, but they had never been to the track. I think this is a track related issue only.

That seems to be the general consensus. I've run mine through tons of autocross runs, and several light track days (it was raining and very cold for both days, so speeds and temps were on the low side), and mine also look perfect after 30k miles.

[Xaeryan]

Originally Posted by M3 09 AND135I 11

Do not remove brake dust shields. They protect wheel bearings from excessive heat.

I'm also a bit curious about this, as I've heard it mentioned multiple times. Is there any evidence to back this up? Don't the BMW motorsport teams run without these shields? What about the guys here who are doing real racing (ER, Berk, scott)? I'd think the heat which could damage the bearings would all be generated at the disc hubs, not the outer area of the disc, in which case two piece rotors with aluminum hats would go a long way in protecting them. But that's just my logical speculation.

[fourtailpipes]

i have only ~20k miles on my '08, but gobs of track time (including more than a few very hot days). everything is in ship shape down there (knock on wood).

[romak47]

anyone try these new titanium shims? ventilated ones.. looks like a good option if you track hard or live in hot climates like arizona or any hot desert.

http://hardbrakes.com/index.php?main...6crqqr65ikrns1

[DriveHard]

Originally Posted by romak47

anyone try these new titanium shims? ventilated ones.. looks like a good option if you track hard or live in hot climates like arizona or any hot desert.

http://hardbrakes.com/index.php?main...6crqqr65ikrns1

HOLY BEJESUS. 239.00 !!!!

Ive got the solid ones...and i though they were expensive, but 239.00 no freakin way.

p.s. they are 1.0 mm thick, New pads / Rotors may have issues with them fitting.

[Groundpilot]

Originally Posted by Xaeryan

I'm also a bit curious about this, as I've heard it mentioned multiple times. Is there any evidence to back this up? Don't the BMW motorsport teams run without these shields? What about the guys here who are doing real racing (ER, Berk, scott)? I'd think the heat which could damage the bearings would all be generated at the disc hubs, not the outer area of the disc, in which case two piece rotors with aluminum hats would go a long way in protecting them. But that's just my logical speculation.

I got this info. from my mechanic. He is a racer, runs a very reputable shop, is very knowledgeable and i dont have a reason not to belive him. We didnt talk about details but i will make sure to talk to him about this more when i see him next time.

[fourtailpipes]

the heat shield helps prevent heat from the brake disc from getting to the rubber suspension bushings and the brake line. as a result of containing this heat, generally they hurt the cooling of rotors and can potentially (slightly) impair the cooling of wheel bearings (to the extent that the air flow impairment is greater than the heat sink effect, which is negligible). the shield also helps to keep brakes free of rain water and debris. most racecars have no heat shields, or shields modified to accommodate some intake of cool air. someone on here posted a DIY for a modified heat shield where the air induction is improved but the shield still left mostly intact. this is probably the best of both worlds.

[GaryS]

Now I'm worried about the splash shield mod we did in front to let more air in. Should we bend them back into place?

Please bear with me if it's unrelated, because I have no idea about any of this stuff.

Here's what I'm talking about:

http://www.1addicts.com/forums/showthread.php?t=527501

[fourtailpipes]

Originally Posted by GaryS

Now I'm worried about the splash shield mod we did in front to let more air in. Should we bend them back into place?

Please bear with me if it's unrelated, because I have no idea about any of this stuff.

Here's what I'm talking about:

http://www.1addicts.com/forums/showthread.php?t=527501

that's what i was referencing above. my guess is that's totally kosher. i'd stick with it (unless you're experiencing any issues). that should do a good job of allowing some more convection cooling to occur while still providing a barrier between the brake heat and inboard components like the brake line and suspension joints. the only cost of that mod should be a possible slight increase in dust/debris getting to the brake, but i wouldn't be too worried about that.

[pixelblue]

I'm the guilty party like fourtailpipes said this is a no brainer. You still have the heat protection as well as getting some air in there. I actually just bend them out just for track days then I bend them back in place for DD.

[GaryS]

Thanks. My installer thought it was a good idea too.

[Groundpilot]

Yep, pixelblue deserves all the credit for this mod. It was very simple but at the same time very smart idea to cut and bend break shields

[pixelblue]

happy to have made a positive contribution in exchange of all the ones I have gotten on this forum

[JB135MDCT]

Originally Posted by DriveHard

HOLY BEJESUS. 239.00 !!!!

Ive got the solid ones...and i though they were expensive, but 239.00 no freakin way.

p.s. they are 1.0 mm thick, New pads / Rotors may have issues with them fitting.

Dremel some holes or slits and your good to go.

[JB135MDCT]

Originally Posted by GaryS

Now I'm worried about the splash shield mod we did in front to let more air in. Should we bend them back into place?

Please bear with me if it's unrelated, because I have no idea about any of this stuff.

Here's what I'm talking about:

http://www.1addicts.com/forums/showthread.php?t=527501

No, Heat sink effect is the same, and better with increased air flow.

[JB135MDCT]

Originally Posted by pixelblue

happy to have made a positive contribution in exchange of all the ones I have gotten on this forum