So at our last local event we had a 3-cone slalom that you'd enter at a pretty good rate of speed. On my last run I wanted to see how much speed I could carry into it before braking hard. The R56 brakes are INCREDIBLE and can usually bring the MINI to a stop very quickly but this time I STOOD on the brakes hard, felt the ABS kick in and midway through it, the brakes felt numb and just about stopped working altogether. It was the first time I'd experienced it and am wondering what caused it.

In my previous runs I'd still stand on the brakes, but it was an earlier entry into the slalom while turning into it and it handled great. This time the brakes started to work, stopped midway and I plowed into the 3rd slalom cone because it just wouldn't slow down nearly enough.

Anyone ever experience it? I wish I had another run afterwards to try and duplicate it.

d
GS27

 

Yeah, this has happened to me once before. I was coming out of a fairly fast slalom into a fairly sharp 90 deg. left-hander, and I blew through the turn. I was afraid I was going to run into the curb of the lot, as it wasn't far from the turn. I ended up getting the car rotated enough to get on the outside of a wall of cones (the outer part of the turn).

This happened on a run where I was pushing the slalom, so I'm wondering if it only happens when the car isn't completely settled and you force it into a heavy braking zone...yeah, that whole turning while braking? Probably not a good thing to do anyway, oops. I never really figured out why it happened, and haven't worried about it anymore because it hasn't happened since then. I definitely didn't try to duplicate it since I didn't want to hit a curb, but would be interested if anybody knows why this happens. I'm all ears.

I do wonder if it's DSC related. Do you have DSC or just ASC? I know my DSC was off, but if there's a significant yaw event, I wonder if the ECU tries anyway to assist in gaining control of the car through the steering (by unlocking the brakes). Typically, ABS should pulse on/off. In this case, it feels like it was just completely off.

??? - sorry that didn't really help, but I thought I'd add that you're not the only one who's experienced this.

John

 

I had the same thing. Going into a 90 to the right. Car was braking then brakes went "off" almost like ice mode in the Elise. I don't have DSC. I did have ASC off.

 

It's called overheating your brakes. Even ABS can't override the laws of physics.

 

Not in my instances. The first time I had it happened, the car was relatively stable, and I had to brake in a straight line into the stop box. We still require stop boxes here in Ontario. The ABS would activate, and kick the pedal back. If I were to be close to the limit, and the ABS was not too active, the car would slow down. If I got into the pedal really aggressively, the car would not slow down enough, as the ABS was releasing braking effort.This has happened at 3 different events. I have had to adjust my driving style, and just be careful to not be too hard on the brake pedal.I am running a 2002 MCS, with HP+ fronts, HPS rear pads. I have talked with the guys from Hawk, and even the guys running Koni Challenge are having similar rear lock up issues.

 

Wow! Brakes that over heat stopping from 50mph. Sweet.

 

Dan

Ron Williams and I both experienced this periodically throughout the season since we left footbrake.

This happens when a rear wheel lifts off the ground while braking, it is basically ice mode since the ECU is thinking you are on ice. If you brake in a 100% straight line, it likely won't ever happen. Its when your coming out of a slalom or around a high speed sweeper with the car slightly unsettled which lifts a rear wheel off the ground. I actually had to take some rebound out of the rear, this helps tremendously because when I first installed the Koni's, I had them near full stiff in the rear and the car was absolutely un-driveable when this "ice mode" occurred on course. I actually nearly ran over a course worker since I couldn't slow down AT ALL and the course worker didn't expect that. Luckily, he ran out of the way, otherwise, Mini would have had a lawsuit since my brakes were basically non-existant.

We actually spoke with the MINIUSA rep at HPT last month, he hadn't ever heard of the issue, so, it must have been something some idiotic engineer decided to add to the R56 even though the temperature is 70 degree's. I could see the ice mode being implemented in temperatures below 40 degree's or so.

Craig

 

The makes sense. I think the Elise does it when the front wheel lifts.

 

If there is an " ice mode", then that would explain a lot of "no brakes" in a sharp, braking turn.I run a completely stock MCS with no suspension upgrades so I can't help the inside, rear wheel lift on braking turns

 

Craig, that's definitely it. Iv'e experienced it one other time and it was in a transition causing the tire to lift; never experienced it braking in a straight line. I wonder if it just kicks in if you're braking longer than usual with the rear wheel up. it's pretty common to lift that rear wheel entering a corner but these times I seemed to be on the brakes hard for longer than usual trying to get it to slow down enough to get through a section.

Thanks for the insight, rear rebound definitely makes sense.

btw, heard any inside word about what the SEB decided on last night's phone call about GS -> DS?

d

 

Dan,

this also happened on the "old" Mini's. Same scenario, hard braking while making a turn.

First noticed this at Fontana Pro in 05 (I think) at the finish box. Had it happen a couple of times after that, always in a part of the course where you were braking hard, and turning.

Damn nanny state mentality of modern car engineers.

 

do the brakes come back when the rear end touches the floor again?

 

No, once in ICE mode you have to release the pedal to get out of it.

BTW, you can also trigger it with a bumpy brake zone or braking just over the crest of a bump and getting the frontend light.

 

I heard someone telling the Mini Rep at HPT of the braking situation, but had not experienced it myself until last month....coming out of a slalom into a right hander the brake pedal became SOLID....would not stop until i completely let off of the brake pedal......I had already been through this section several times....must've been too far over the edge.....I do left foot brake.