135i Calipers - melted dust boots

[joeo]

Seems like removing the dust shield would result in much better cooling. Do we know if the dust shield is really used as a heat sink for the wheel bearing?
So far, it doesn't sound like the problem has ever occurred with a 100% stock setup.
Thanks for the help!

[Groundpilot]

I wanted to remove my front dust shields, but my mechanic who is a racer and is very knowledgeable, told me that they protect wheel bearings from overheating.
I would just go with Pixelblues mod that doesnt cost anything and is very effective IMO.

[joeo]

That makes sense - more to keep the radiant heat from the rotor away from the other parts (bushings etc.)
Thanks. I'll get bending.

[Dackelone]

Originally Posted by joeo

Seems like removing the dust shield would result in much better cooling. Do we know if the dust shield is really used as a heat sink for the wheel bearing?
So far, it doesn't sound like the problem has ever occurred with a 100% stock setup.
Thanks for the help!

BMW has modified the splash shield design on the new F30. Take a look...

[DriveHard]

Originally Posted by Dackelone

BMW has modified the splash shield design on the new F30. Take a look...

Attachment 656097

Attachment 656098

Pixelblue and I have been dealing with these backing plates since last year..I designed a set of one off plates with a scoops and pixelblue simply cut his and bent it over creating the same kind of result.. what Dack posted was very interesting to me as that was my basic design excep BMWs looks a whole lot better as they are stamped from one piece and mine are rivited together.

I ordered a set of the f30 backing plates already and are waiting for them to come in as they were not available yet.. 1 side should be here soon and i am expecting the other side in like 2 weeks.

I am guessing that they will bolt up pretty easy ( it is only held on with 3, 10 or 8 mm bolts. I have high expectations for this mod to solve alot of people brake cooling issues for daily driven weekend track rats...

and as a side note; i have tracked approx 540 miles, thats about 12 events, and about 15 or so auto x's. The first three track events were on STOCK pads and bent shields and i sufferd NO issues.. The rest of the events were coolcarbons with Titanimum shiels (.05mm if i recall) and bent shields or my custom cool brake plates..

I have looked at my calipers/ pistons almost after each event and i suffer no issues. ( im no mario andretti, but i aint slow either LOL )

I do have an advantage as my VMAX is less than a 135 ( about 15 MPH at the end of most Straighaways) and my car is about 200 to 300 lbs less also. so that may be playing into things, But as my screen name says... I do DriveHard...

ill let everyone know about the plates whan they come in

Regards.

[FORMnFUNCTION]

Subcribed!...waiting for the shields!

[DriveHard]

Ok i got a left... waiting for the right... ill compare to orig when i get home as i have a few laying around from when i made my prototype shields last year.

they have a definite scoop in them, almost 3 inches out from the vertical plane.

Stand by, as i will take a pic tonight

[pixelblue]

Alex, that's great. can't wait to hear the final verdict

[DriveHard]

i got the plate installed !!!

i started a new thread..

see here >>> http://www.1addicts.com/forums/showthread.php?t=663510

they worked beautiful !!

[joeo]

Just a data point - no issues (discolored calipers) with a stock setup (stock pads, rotors and calipers).

[joeo]

Looks like the stock pads have worn unevenly - has anyone seen this occur? Calipers looks fine, but the dust boots have some small cracking in them.

[pixelblue]

Joe, I've seen pads on one side worn more but never seen this before. it seems you might have uneven piston pressure. that's my wild guess

[pixelblue]

actually take a look at how high each piston is sitting. you can clearly see one end is higher than the other and the same for the other side. this definitely looks like uneven piston pressure. not sure why. maybe air?

[joeo]

Yeah - I noticed that too. It could be air - I will bleed it.

[Focusedintntions]

Joe I got wear like that before I rebuilt my one caliper. After the rebuild I got even wear. Coulda beem though that the bleed after the rebuild fixed it too.

[joeo]

It happened on the other side as well. At least it's consistent.

Looks like it's the outside boots the have the most cracks in them - perhaps the outside gets hotter than the inside. Splash shield was bent - not Ti shims, although I received them in the mail a couple days ago.

Kori - do you think the BMW perf rotors lowered your temps? I'd love to go with DTC70 pads, but I don't want to cook calipers.

[pixelblue]

Joe, I don't think the performance rotors are worth the dough. couldn't tell if the temps were lower although I was braking harder than last time. one thing I did notice was that it seems these rotors chew through pads quickly. I think oe rotors work fine and are cheap enough to replace once a year just make sure you get either motul rbf600 or castrol srf for brake fluid. also I suggest try the ferrodo's first and work your way up to dtc70's if you don't want to go through pad swaps for track/DD. my .02

[joeo]

So far I haven't had any issues with the ATE fluid - I just make sure it's fresh, although the RBF is about the same price. Changing brake fluid isn't going to help the dust boots. So far, it's only Summit Main that seems to be an issue for the brakes. Do you think the ferrodo pads run cooler?

[R3ctivision]

Sorry to bump, but I just took my 135 to Laguna Seca last weekend. I had upgraded to stainless steel brake lines, Motul fluid, and Hawk HT-10 race pads, as I've had a history of atrocious fade and actually BENT brake pads on my old E36 there.

Well, lo and behold I have discolored calipers, slightly yellow/greenish tint to them. I haven't swapped back to stock pads yet and don't have access to a home garage to do the swap myself for a few months. What's the likelihood I toasted my whole brake system, and will need to do a total caliper rebuild?

I did drive about 350 miles of highway/street after the track day, and haven't had any noticeable issues, except that the first time I press the brake after a dead cold startup I hear a small metallic popping sound, and then not again until the next day on a dead cold start. Is this likely to be a safety issue if I melted dust seals/discolored calipers/possibly cracked a piston?

Dunno what the best solution is to this aside from not tracking the 135, as I don't want to spring for a BBK. Sigh. In any case, the damage might already be done...

[Focusedintntions]

Originally Posted by R3ctivision

Sorry to bump, but I just took my 135 to Laguna Seca last weekend. I had upgraded to stainless steel brake lines, Motul fluid, and Hawk HT-10 race pads, as I've had a history of atrocious fade and actually BENT brake pads on my old E36 there.

Well, lo and behold I have discolored calipers, slightly yellow/greenish tint to them. I haven't swapped back to stock pads yet and don't have access to a home garage to do the swap myself for a few months. What's the likelihood I toasted my whole brake system, and will need to do a total caliper rebuild?

I did drive about 350 miles of highway/street after the track day, and haven't had any noticeable issues, except that the first time I press the brake after a dead cold startup I hear a small metallic popping sound, and then not again until the next day on a dead cold start. Is this likely to be a safety issue if I melted dust seals/discolored calipers/possibly cracked a piston?

Dunno what the best solution is to this aside from not tracking the 135, as I don't want to spring for a BBK. Sigh. In any case, the damage might already be done...

If you've discolored the calipers you've probably melted the dust boots. The popping sound you hear is probably just the pads moving within the caliper as you switch from reversing to moving forward. Changing your pads to get in there is easy and you can realistically do it any parking spot/lot. Your caliper is fine, and the pistons for right now are fine as well. It takes several heat cycles before the pistons really become an issue.

As far as the rebuild goes, you can get new dust seals if you like. So far i've tried 2 sets of the turner ones and they melt just as fast as the OEM ones. The RacingBrake seals seem to handle the heat the best and don't turn to liquid after a single weekend. If you wanted to rebuild the whole thing, the RB pistons/seals kit isn't a bad way to go. It's what I've used after mine went to dust and I've been very happy with them.

I've rebuilt my calipers 4 times. First two times were putting in turner seals and boots which didn't last any longer than OEM. The last couple times were installing the RB seals. Did a couple weekends with them and took them apart to do a full inspection to see how things were holding up with the new pistons and seals for Warren. Happy to report they held up great.

If you don't track a ton, I think you'd be happy with the RB solution. However if you're planning on tracking more than say 1 a month. You may just want to bite the proverbial bullet and go ahead and invest in the bbk. Maybe keep and eye out for used set on the e90 forums?

[R3ctivision]

Thanks, that helps a lot. I'm glad to know it doesn't seem to be a safety issue for now. As long as it is okay on the street... I'll probably take a long hard look at this when I get a chance to swap pads. I only track around 2-3 times a year, although that might change!

[02rsxpilot]

Originally Posted by joeo

I'm wondering if it has happened with a stock setup. From what I've seen/experienced, it only happens with race/track pads. I wasn't clear in my original post - the photo is from a caliper that was used with HT-10 pads.

I'd like to know if doing track events with a 100% stock setup has led to any problems like this.
Thanks.

For the record, my dust boots began failing on a completely stock setup. I ran two events like this before switching to DTC-70s up front.

Has anyone found a good solution? Not going OEM unless BMW does it for free under warranty/free maintenance because it's just going to happen again. I'm a little worried about reports on here that the RB dust boots fail after exposure to the cold (this is kind of funny when you think about it). The Brembos perform so well outside of this brutal design flaw that spending huge cash on a BBK just isn't an appealing option for me.