My new StopTech/Apex setup on 128i

[dcaron9999]

To Nate301 + Jafo1701 ...
Im also getting brake fade from my stock 135i calipers and Carbotech XP10 pads towards the end of my 20-minutes sessions. Part of it might be due to the HardBrakes.com Titanium Heat shields, keeping too much heat into the pads. Pedal is allways firm, but fade is noticeable, so I brake earlier towards the end of my session. Not totally happy with my current brake setup, which is a work in progress. It includes "winged" F30 brake dust shields for better cooling, Motul RBF-600 fluid which I flush twice a year, and blank OE rotors.

Nevertheless, budget is limited, and I prefer the above "gradual fading" behavior than burning up/crumbling my stock 135i caliper boots and pistons, or soft pedal/sudden lack of brakes. Next year, if I still own the car, and still into lapping events, coilover suspension is in order, and maybe a front BBK if I dont sort out the brake fade issue by then.

For the short term, Im looking at better (more heat tolerant) endurance front pads, such as Carbotech XP12, or PFC 08 compound (if I ever get a set to test from Speed-Freaks.net).

So to conclude, your Titanium shields may be worsening your problem on the entry level Hawk HP+ pads at the track, since there is more and faster heat build up in the pad. You are probably surpassing the pad's recommended operating temperature range (ask me how I end up with severe brake shudder and destroyed a set of "Cool Carbon" brake pads last year in one track day).

[TheSt|G]

The posts above are why I'm a broken record when it comes to the 135i brake setup having little in common with a real BBK.

[jafo1701]

I may eventually upgrade to the Racing brake larger 2 piece rotors. Given I've already spent the money on the Racing brake Caliper Rebuild kit. I thought about keeping the Ti shields, but had the same thoughts as dcarron. I think heat build up would be worse. I'll see how this year goes and make a determination as I go. Given my driver skill I feel I should be good for this year. How easy is it to upgrade to the F30 shields. Does anyone make them so I can can just remove my current shields and bolt on the F30 ones? I guess every little bit helps.

[E82MSport]

Originally Posted by jafo1701

I may eventually upgrade to the Racing brake larger 2 piece rotors. Given I've already spent the money on the Racing brake Caliper Rebuild kit. I thought about keeping the Ti shields, but had the same thoughts as dcarron. I think heat build up would be worse. I'll see how this year goes and make a determination as I go. Given my driver skill I feel I should be good for this year. How easy is it to upgrade to the F30 shields. Does anyone make them so I can can just remove my current shields and bolt on the F30 ones? I guess every little bit helps.

This might answer your shield questions
http://www.1addicts.com/forums/showthread.php?t=663510

[nate340]

Jafo1701 - So you've yet to have the car on track with the RB SS pistons installed? I feel the stock aluminum pistons with their ceramic caps do a better job isolating the brake fluid from the heat of the brake pads and preventing it from boiling. I’ll be very interested in hearing your impression once you've had the car out on track.

Stock ceramic capped pistons, hawk pads and titanium shims with RBF 660 fluid has so far worked the best. Once I changed to the RB SS pistons I noticed my brake fluid boils and my pedal goes soft much sooner.

Also I’m running a square setup with BFG R1’s in a 225/45/18. My car only has a Cobb tune which I usually run Stage 2 aggressive as I also have downpipes. I imagine no more than 360 WHP. I’ve been tracking for about 7 years and am quite competitive often passing much “faster” cars while out on track even with my brake issues.

dcaron9999 - I understand what you’re saying. You feel the titanium shims are keeping the heat isolated to my HP+ brake pads and causing them to overheat and fade which is causing me to stay on the brakes longer and building up more heat in my braking system causing the fluid to boil.

I’m not sure I 100% agree as the shims are designed to stop heat transferring into my brake fluid but I’m willing to experiment a bit. I suppose the only options I have is to go to a more aggressive pad like a DCT-70 or something similar or stick with the HP+’s and remove the shims and see how they perform.

Appreciate all the advice. I'll be back on the track hopefully within a week I'll update my situation then.

[TheSt|G]

Originally Posted by jafo1701

I may eventually upgrade to the Racing brake larger 2 piece rotors. Given I've already spent the money on the Racing brake Caliper Rebuild kit. I thought about keeping the Ti shields, but had the same thoughts as dcarron. I think heat build up would be worse. I'll see how this year goes and make a determination as I go. Given my driver skill I feel I should be good for this year. How easy is it to upgrade to the F30 shields. Does anyone make them so I can can just remove my current shields and bolt on the F30 ones? I guess every little bit helps.

The install is super easy. You take off the old ones, lay them over the new ones, drill a hole or two in the new ones, and then mount the new ones back on the car. Depending on mileage, you might want new hardware as well.

[dcaron9999]

Originally Posted by nate340

dcaron9999 - I understand what you’re saying. You feel the titanium shims are keeping the heat isolated to my HP+ brake pads and causing them to overheat and fade which is causing me to stay on the brakes longer and building up more heat in my braking system causing the fluid to boil.

I’m not sure I 100% agree as the shims are designed to stop heat transferring into my brake fluid but I’m willing to experiment a bit. I suppose the only options I have is to go to a more aggressive pad like a DCT-70 or something similar or stick with the HP+’s and remove the shims and see how they perform.

Appreciate all the advice. I'll be back on the track hopefully within a week I'll update my situation then.

Im not sure that you may be boiling your fluid. Brake fade is due to overheating your pads. You and I are accelerating the temperature build up in the pad, because the heat has nowhere to go except to the rotors. Heat is not being transferred to our calipers due to Titanium heat shields, so the pads get hotter, more quickly. IF you look at operating temperature range specs for track pads like Carbotech or Hawk, they all have specific heat ranges that they are designed to work within.

Personally, I think I am overwhelming my XP10 pads more quickly now since I moved from 225/40R18 front tires to 255/35R18 EHP tires, so the front brakes have more work to do now due enhanced adhesion in the front. Im not getting a soft pedal (boiling fluid), but I do need to step on the brake pedal harder (brake pad fade), and brake earlier.

This is why I want to move up from XP10 (1475* max temp) to XP12 pads (1850*F max temp). XP20 pads can endure up to 2000*F.

Hawk DTC60 and DTC70 pads can both handle 1600*F.

Ive read somewhere that the Hawk HP+ does not have a high enough max operating temperature to work well on the track for most cars. The HP+ is an appropriate street pad for owners who want the ability to drive them a little harder than the typical street pad.

[kobeballer96]

Originally Posted by Donny Rino1

Sooooooo I have to ask this ....why would you spend all that money on a car that isn't capable enough to use those brakes to there fullest ?

lol must not drive your car hard or have any track experience.

[kobeballer96]

Originally Posted by DurimOne54

I agree with this, however not in the way it was addressed. I always found it unusual when owners add a BBK to a vehicle with poor performance. At that point is seems purely Cosmetic/Aesthetic. Why does a 128i require that much stopping force?

I know I will get the typical responses, "It's his car he can do what he wants with it" but I would just like to know the reasoning behind this.

No offense to OP. I am asking sincerely out of curiosity.

Yes when reaching fast speeds yes, this my 128i. I cannot afford a BBk at the moment, but I'm running Pagid track pads and stoptech rotors with motul brake fluid. You'll notice that we can obviously reach fast speeds. Here's my video.

[jafo1701]

Nate, haven't tracked the car yet since I did the rebuild. My rubber dust boots were shot and ceramic pistons were just starting to crack. I was running the ti shims too. I thought about a BBK but just wasn't in the budget. I run 235/255 with RS3s. I have the PPK1 installed so only a little boost in power over stock. My first track day of the year is this coming Monday. I'll report back after the track day.

[nate340]

dcaron9999- We’re clearly having two different issues, I agree you are having what sounds like brake fade but I’m 100% sure I’m boiling my brake fluid. It’s possible I’m also exceeding the HP+’s range a bit causing a bit of fade but my primary issue is once my brakes are nice and hot after 5 laps or so laps the brake pedal goes soft. I barely put any pressure on the brake pedal and it just sinks for a heart alarming few inches before it firms up sometimes the pedal bottoms out before I’m able to reach the required pressure for the necessary braking force.

Also if I’m unable to run at least 2 cool down laps before coming into the pits even after letting the car sit in the pits for 30min as soon as I get in and start the car the brake pedal goes straight to the floor as though there is significant air in the brake lines. I assume this is caused by excessive heat in the rotors and pads transferring through the pistons into the brake fluid causing significant air in the lines. Also with me bleeding my brakes before every track event I always see numerous pockets of air coming out from the calipers.

[jafo1701]

Here's my initial report from my track day yesterday. I haven't taken em apart yet to check my dust boots and pistons but the brakes held up fine. No fade and no boiling of the brake fluids...And I was really hard on the brakes towards the end of the day. Only thing is that I almost completely disintegrated my Carbotech XP10s. So bad that I didn't chance it on the last session and call it quits. I had Carbotech two day air me some XP12s so I could run this weekend again. I decided to go with XP10s in the rear. Currently have stoptech street performance in the rear. They held up fine, but don't think they'll make it another track day.

[dcaron9999]

Originally Posted by jafo1701

Here's my initial report from my track day yesterday. I haven't taken em apart yet to check my dust boots and pistons but the brakes held up fine. No fade and no boiling of the brake fluids...And I was really hard on the brakes towards the end of the day. Only thing is that I almost completely disintegrated my Carbotech XP10s. So bad that I didn't chance it on the last session and call it quits. I had Carbotech two day air me some XP12s so I could run this weekend again. I decided to go with XP10s in the rear. Currently have stoptech street performance in the rear. They held up fine, but don't think they'll make it another track day.

Wow! If you did this to your XP10's, you must be hitting pretty high speeds where you lap your 128i. Im faced with a similar situation on my 135i and 255/35R18 square setup, and the same CT XP10 pads. I noticed that Im getting the front pads to fade sooner, now that they are 50% worn, and I run wider tires up front. The XP10 front pads have turned white.

I just got a fresh square set of Dunlop Direzza ZII 255/35R18 installed this morning. Im eager to get the front brake fade issue addressed more than ever. If I dont get my beta PFC 08 brake pads within 2-3 weeks, Im ready to pull the trigger on XP12 front pads, while I keep running my XP10 rear pads.

It kind of sucks that Carbotech never has the 135i pads in stock, and have to cook them or you (5 biz days for CT to cook them + 7 biz days for shipping, duties, brokerage).

Where are you getting your XP12 front pads, and what is your estimated delivery date?

[nate340]

Maybe my car has something wrong with it. I just bled my brakes in preparation for my track day tomorrow and noticed that when i pump the brake pedal it firms up nicely but then it slowly compresses. I've always thought the brakes were soft but just assumed that was the feel BMW was looking for. do other 135i's have this issue?

[dcaron9999]

Originally Posted by nate340

Maybe my car has something wrong with it. I just bled my brakes in preparation for my track day tomorrow and noticed that when i pump the brake pedal it firms up nicely but then it slowly compresses. I've always thought the brakes were soft but just assumed that was the feel BMW was looking for. do other 135i's have this issue?

Never noticed the sinking pedal. Been using a Motive Power Bleeder for years. Worthwhile investment for about $55USD. You typically need two 500ml bottles of your favorite DOT 4 brake fluid into the Motive bleeder. You pump the bottle up to 15 PSI, and your car's brake fluid reservoir can never get dry/or insert air into your system. As a bleed bottle, I use an empty clear water bottle with two holes in the lid; one for the 1/4" clear bleed tube that you can buy at the local hardware store, one for air pressure escape.

Is your brake fluid level stable in your reservoir? This would eliminate the possibility of a leak somewhere in your system...

Dumb questions:
#1 - Are you executing your bleed sequence from the passenger rear, driver rear, passenger front, and driver front?
#2 - As you open the bleed screw, are you tapping your calipers with a rubber mallet to let out any tiny air bubbles?

Quick ECStuning brake bleeding DIY video:

[nate340]

I actually own and use a Motive Power Bleeder I enjoy how quickly it pushes the fluid through the caliper much quicker than having someone pump the pedal.

I don't tap the calipers with a rubber mallet but do understand how that would be beneficial and will certainly do it in the future.

So when everyone else pumps the brake pedal in a 135i does it firm up then slowly sink for a few inches? while driving it isn't noticeable.

[jafo1701]

Well I rebuilt the rear calipers with the racing brake kit yesterday and installed Carbotech XP 10s. Installed the Carbotech XP 12s up front and inspected the boots and pistons. Pistons of course are perfect. Except for one dust boot they are all in perfect shape. One has a small cut in it, but no scorching or burning makes in the boots. Back at the track on Monday I'll report back. One thing I did notice while bedding in my track pads, I no longer have the rear wobble when hard braking. My old set up was Xp 10s up front and stoptech street performance in the rear. My guess is my XP 10s were out braking my stoptechs.

I also had the motive bleeder and have zero problems. Next time I have to try tapping on the calipers. thanks for the tip.

[jafo1701]

Originally Posted by dcaron9999

Wow! If you did this to your XP10's, you must be hitting pretty high speeds where you lap your 128i.

Where are you getting your XP12 front pads, and what is your estimated delivery date?

I'm in a 135i, my afternoon session I was pushing a lot harder. A lot of good drivers our intermediate group. I was just trying to keep pace. Track day was at the Autobahn. There again on Monday. I got the pads direct from carbotech. Called em monday, got em Wednesday. Got em installed on Wednesday afternoon.

[dcaron9999]

Originally Posted by jafo1701

Well I rebuilt the rear calipers with the racing brake kit yesterday and installed Carbotech XP 10s. Installed the Carbotech XP 12s up front and inspected the boots and pistons. Pistons of course are perfect. Except for one dust boot they are all in perfect shape. One has a small cut in it, but no scorching or burning makes in the boots. Back at the track on Monday I'll report back. One thing I did notice while bedding in my track pads, I no longer have the rear wobble when hard braking. My old set up was Xp 10s up front and stoptech street performance in the rear. My guess is my XP 10s were out braking my stoptechs.

I also had the motive bleeder and have zero problems. Next time I have to try tapping on the calipers. thanks for the tip.

Excellent!

Seems like you are working the kinks out. Can you share the DIY you used to rebuild you calipers?

I have a fealing your XP12 front and XP10 combo will work well, and tolerate the abuse better. This is my next move too (if I dont get the PFC-08 pads this month).

Anish from Speed-Freaks.net has recommended I check my XP10 pads for glazing, and if found, sand the pad surface down a little.

[jafo1701]

Originally Posted by dcaron9999

Excellent!

Seems like you are working the kinks out. Can you share the DIY you used to rebuild you calipers?

I have a fealing your XP12 front and XP10 combo will work well, and tolerate the abuse better. This is my next move too (if I dont get the PFC-08 pads this month).

Anish from Speed-Freaks.net has recommended I check my XP10 pads for glazing, and if found, sand the pad surface down a little.

I didn't follow any specific DIY just kind of took it out and did it. I can write one up if you want. It's relatively easy, just time consuming. Just need an air compressor with an air gun and some channel locks for the pistons, Pick tool for dust boots and seals removal inside the Calipers. A 14 mm wrench for the brake line. I have a set of Flare wrenches that worked perfect. Then 3/8" vacuum cap to seal of the brake line. Then a Hex bit set to remove the Calipers from the car and Star bit set to more remove the brake pads.
I wanted to go PFC 08 as my next pad, but didn't expect to burn through my XP10s so fast. I needed pads now, because of another track day Monday and I would be leaving to spend the weekend in Chicago on Friday. So I needed em by Thursday. Cudos to Carbotech for great service and getting them to me on Wednesday. I didn't know how fast Speed Freaks could get me the pads. I ran PFC 06s on my E36 M3 and loved em, plus they lasted forever. I'll see how the XP 12/10 combo works and how they wear. Depending on that I may go with the PFC set next year.

[dcaron9999]

Originally Posted by jafo1701

I didn't follow any specific DIY just kind of took it out and did it. I can write one up if you want. It's relatively easy, just time consuming. Just need an air compressor with an air gun and some channel locks for the pistons, Pick tool for dust boots and seals removal inside the Calipers. A 14 mm wrench for the brake line. I have a set of Flare wrenches that worked perfect. Then 3/8" vacuum cap to seal of the brake line. Then a Hex bit set to remove the Calipers from the car and Star bit set to more remove the brake pads..

I suppose there is no way to do this with the brake line under pressure and caliper and still on the car, but off the caliper bracket? Do the pistons easily come out - how are they held in - can they be screwed out?

Originally Posted by jafo1701

I wanted to go PFC 08 as my next pad, but didn't expect to burn through my XP10s so fast. I needed pads now, because of another track day Monday and I would be leaving to spend the weekend in Chicago on Friday. So I needed em by Thursday. Cudos to Carbotech for great service and getting them to me on Wednesday. I didn't know how fast Speed Freaks could get me the pads. I ran PFC 06s on my E36 M3 and loved em, plus they lasted forever. I'll see how the XP 12/10 combo works and how they wear. Depending on that I may go with the PFC set next year.

You did get the CT pads extremely fast. Congrats! I was told by another vendor that the 135i caliper pads were not in stock at the Carbotech warehouse, and 3-5 biz days were needed to produce them.

Please post back your results once you hit the track with XP12 pads - really looking forward to your review! Have you had fitment issues - do the CT XP pads fit loosely in the caliper, and does the brake sensor cutout have paint and glue stuck in it (not that it matters on a race pad but do the XP12 even have the cutouts)?

[fe1rx]

From my OHLINS post:

BRAKE INSTALLATION AND BRAKE PISTON BOOT REPLACEMENT

Not strictly part of the Ohlins installation, but a necessary part of the project – the front brake calipers needed the dust boots changed on the pistons because they had become charred from previous track days. I had removed the calipers early in the process, which made the replacement of the piston boots much easier. I had also fabricated a set of piston wrenches to assist removing and reinstalling the pistons (4 different sizes are needed to cover both the front and rear calipers). They definitely made the task of removing, cleaning, lubricating and installing the boot easier.

Attachment 1010225

Another simple tool was fabricated from a piece of 2 x 4 lumber, cut to fit in the space normally occupied by the rotor. With this in place, a few careful puffs of compressed air extend the pistons for removal. Without it, inevitably one piston will pop out easily, then the rest won’t budge. The correct width of wood allows all pistons to fully extend without any of them becoming unsealed. The wood also provides a cushion so that the fragile phenolic piston nose is not damaged by slamming into its opposite piston.

Attachment 1010226

I lubricate the pistons with a light coat of Permatex Ceramic Brake Lube before installing them. I believe this helps protect them from galling in the cylinder bores. The piston seal keeps the lube away from the fluid, but in any case the lube is brake fluid compatible.

Attachment 1010227

Although I have Hawk DTC track pads, at this moment I am installing OE brake pads, which will be changed before heading to the track.

Attachment 1010228

Additional Notes:

1) depress your brake pedal half way and block it there before removing your calipers. This will prevent fluid from leaking out of the lines.

2) don't use pliers of any kind on the piston as you will damage the sealing surface. My fancy piston wrenches make life easier but are not essential. Once the pistons are mostly out they can be pulled out with your fingers.