My new MCS came with the JCW BBK/drilled & slotted rotors. I really didn't want them at all as other than adding some bling I'm really not hearing the true benefit gained by them. On my last '09 MINI I just used the stock calipers/rotors with EBC pad upgrade (and race spec fluid) - as far as I was concerned the setup seemed to work just fine for me with ample stopping power when I needed it during hard braking. Believe it or not, I used it as a negotiating point that pretty much led me to getting the entire JCW BBK setup for free because the dealer was unwilling to remove them and replace with stock (which I knew they couldn't do anyway). They were of course pretty astonished I would ask for such a silly "downgrade" but I figured why not try the bluff, worst they could say was "no". Surprisingly the bluff worked (probably because I was there hammering away at them for 6-hours). However, with all of the reviews in posts I've seen, some good, some bad, I'm getting a bit concerned I'm now doomed to high long term maintenance costs due to excessive pad and rotor wear. Is this the case? Do I need to plan for increased long term maintenance costs due to higher frequency replacements than stock? The JCW BBK does seem to have pretty good stopping power (but I figure that's probably more due to the upgraded OEM brake pads than the kit). Please let me know as I'd really appreciate the advice. If this is just going to become an expensive long term cost issue, I may seriously consider going back to stock or other cheaper alternative at first opportunity? Thanks in advance!

 

I've had my JCW BBK installed for just under 10k miles at this point, and am not seeing any evidence of premature wear on the pads or rotors. From the look of it, I still have easily 80% of the pad material left at this point. My JCW BBK included cross-drilled and slotted rotors too, which I could take or leave. I'll replace them with normal JCW blanks when they wear out down the road. Where are you seeing reports of premature wear?

FWIW, I've had stock brakes, EBC pads and upgraded rotors on stock brakes, a Wilwood BBK, and this JCW BBK on my car so far (long story). JCW brakes are clearly an upgrade from the stock setup if you need them (ie. their increased heat capacity). Even if you don't need the extra mass, it's certainly not going to be worth your while to swap them to stock parts. It would take a lot of brake jobs at $12 a rotor less than JCW rotors (for Centric 125 series replacements) to bridge that gap. Even with genuine MINI parts, JCW rotors are less than $20 more apiece - worst case (from the dealer). Aftermarket pad prices are pretty much a wash between the two, and the stockers are $40 more a set on the JCW side.

--Matt

 

Hey, so you don't keep worrying about it, I'll trade you my stock MCS brakes for your JCW kit.

 

Thanks, Matt. I appreciate it. I'm reading on track sites they are prone to cracking and excessive wear. However, if you're not having problems, are not hearing of problems with them on the road, and the maintenance costs aren't significantly higher, that's definitely relieving to here. Thanks for the info

 

I've definitely seen at least a few complaints of the boots on the calipers melting under track conditions. They're reportedly cheap and easy to replace, though. I've also come across one report of melted pistons on a race/rally car with track pads. He ended up getting metallic pistons and they reportedly solved his issues.

These issues are not common on street driven cars as far as I have seen.

--Matt

 

All of the issues mentioned are caused by very high heat, which is generated by frequent hard braking at high speeds. Those conditions happen at the track, not during regular street driving.

 

Did anyone ever come up with replacement pistons that can better hold up to track duty without melting?

 

I saw somewhere that the OEM pistons can be replaced with metal pistons from Brembo.

The 6-pot Brembo calipers used in the GP2 are the same as in the BMW 135i. There is a discussion about those pistons here: http://forums.racingbrake.com/showthread.php?t=859

 

Those are the Brembos that come on the GP2 (6 pistons). The JCW 4 piston Brembos are what I was referring to.

 

robbo_mcs had his fabricated at a shop: https://www.northamericanmotoring.co...ml#post3745323 (post #20)