Cooper S brakes

[KLF]

Hello there,

This is my first post (woohoo!) so I don't know whether this has been covered already:-

Does anyone know whether the brakes are any different on MCS to the MC/ONE, as I asked my dealer to have a look at my MCS brakes(1k miles) because I find them very poor, ie soft spongey feeling - they seem as if they need warming up before you get any sort bite, and they seem as if the abs comes on when hardly pressing the pedal.
I got a mini one as a courtesy car and found it had more braking power than my MCS, good bite from cold and the pedal seems more solid, this on a car that has 73hp less than mine!
So my dealer did a so called 'braking efficiency test' saying they were ok - my reply was I will continue with them to see if they get any better.
Now with 2600 miles on clock, don't get me wrong they stop the car but don't seem to be getting any better, so perhaps its just my driving.
Another visit to the dealer is booked for next week, any comments from other owners would be nice - as I feel like ordering the Tarox big brake conversion (mmmmmm!)

[Jazzy Jase]

Do you have the 17 inch wheels?

I find the ABS comes on quite often especially when braking on a bumpy road.

I think the weight of the 17 inch S spokes is to blame.

[BruceK]

Quote:

Originally posted by KompressorChris
...
Does anyone know whether the brakes are any different on MCS to the MC/ONE, ....

All MINI models, (One, Cooper, and Cooper S), use the exact same brakes.

Other members have also noticed a difference from car to car however. As Cooper_S noted, it may be due to wheels, tires or even whether there is some air trapped in the brake lines causing the difference.

[KLF]

Yes 'Cooper_S', I run the 17 inch S spoke (11.4kg)

[Marcus-SanDiego]

I've found that the MCS brakes are underpowered. It could be these heavy rims and tires we have (S-Lites with Pirelli runflats), but I don't know. I will be swapping out rims and tires by the end of the year, then I will know for sure.

At that time, if I determine that the brakes just aren't up to snuff, the Brembos are getting put on. I had them on my BMW and they were amazing.

[Simon Jackson]

At last, someone else with my problem!!! My Car has been back in twice already for the brakes to be looked at. First time they found no fault, but I persisted. Service Manager has since taken my car out again and agreed, the brakes could be better. I also have access to a Cooper that stands on its nose under initial braking, with a much firmer pedal. My Dealer has contacted BMW and is awaiting a response. Please e-mail me your details for my records, I will let you know the outcome! Don't get me wrong, the brakes work fine, just not as solid pedal as the Cooper. Miniguy or here2help able to comment?

[RedCooperS]

I have an August build Cooper S with the 17" S lites and Good year all season run flats. It stops great! I have a BMW Z3 2.8 Roadster and a 528i, and a March S2000 race car, I wouldn't expect the brakes to be any better on the S than they are. Only have 600 miles so haven't taken it to a day at the track yet but I expect from some hard runs and stops on streets that they will be just fine.

[Simon Jackson]

Its not that they aren't good, the Cooper and One brakes do pull up sharper, with a stiffer pedal. The only way to notice is to drive an S then A Cooper or One!

[Viscount Charles]

I agree 100% - when I test-drove Coopers and ONEs, I noted the sharp brakes and firm pedal action. Every S I've driven, including my own, have a spongier pedal and a more progressive action. It doesn't bother me, but I find it difficult to believe it's just down to different wheels/tyres.

[Simon Jackson]

ttt. Anyone else had this?

[KLF]

Just to give everybody an update on my mcs' visit to the dealer yesterday -
This was the second time I have asked them to look at the braking system, so they did their braking efficiency test on rolling road saying it was fine again!
After I had asked them to check if there was any air in the system causing the spongey feeling in the pedal, I got some interesting news! - according to the service guy 'I should not compare my brakes to the mini one loan car because they are totally different' apparently the Cooper S has a harder compound brake pad so will never have the same bite as the mini one/cooper.

So they would like me to drive their Cooper S demo to compare mine too (this also has 17" wheels) - as I asked the service guy what he thought about the heavier 17" wheel causing the braking system to be less effective, he said he would have to speak to BMW about that if I still was'nt happy after my next visit.

So, I will keep you posted.

[mini2mad]

I am interested in the brake comments re the S and other Coopers

I took my Cooper S (2500 miles) into my Dealer 10 days ago as I felt the brakes were not good compared with the Cooper which I also have.

They checked them out and said fine. No difference !!

They are certainly not the same as the Cooper which I find sharper and give more confidence. This is after a yr and using the car on the Track, Sprints and Hill Climbs - where you need good brakes.

The S is a much faster car and should have better brake system then the "lower" models.

I am considering an upgrade before taking to the track in the spring. Any suggestions ??

[Wobert]

This thing about heavier wheels affecting braking is a misnomer.....heavy wheels affect "unsprung" weight, which in turn affects the reaction of the suspension, thus affecting the handling.

Lots of things can affect braking performance....

The compound of the tyres....and the friction coefficient at the contact patch. This could be why the ABS is coming in "too soon". Is the road wet or dry, oily?

Air in the system....air is compressible....brake fluid is not....hence the "spongy" feel. Get the dealer to bleed the system, working on each half of the split circuit in turn.

Pad compound....the energy to be dissipated when braking goes up with the square of the speed....the Cooper S is marginally heavier than the other models...and much faster...this equals more energy. It may be that BMW decided to fit a "harder" compound to get the required life. Has anyone compared friction material between One / Cooper & Cooper S?

Hope this helps....

(PS: I am a Professional Engineer!)

[Wobert]

It's all about overcoming inertia.......the greater the inertia....the more power you need to achive the same acceleration.

Remember the wheels are part of the car....and should accelerate at the same rate....unless they are spinning.

Thinking about the friction material......my comments are most probably right...a heavier faster car will wear the pads quicker....to achieve a set life prediction to meet the service intervals...it could be that a harder material was specced to cope with the wear....harder material equals less friction (generally).

[Hapo]

...the most NOTICABLE difference will be in the handleing....but there is notable improvment in all areas with less unsprung wieght...


...the most remarkable improvment one can make on a sporting or racing motorcycle is to upgrade the wheels and brakes, largly to shed excess mass....ROTATING unsprung wieght is of especial signifigence...just think of the gyroscopic effect...the greate the mass, the more difficult ot will be to dissapate engery or overcome inertia....ie turn, stop, or accelerate...

...conversly, a bigger wheel puts more rubber on the road, to help better over come these things...


...as noted previously, the design paramaters of the supporting hardware are largly what will determine the "point of dimminishing returns" as to what loads can be supported...ie, how big and fat the wheels can be...

...different conditions might dictate that different loading characteristics are more or less desirable than others...this is why we don't put on skinny knobbies and head for the drag strip, or put on fat slicks for a trail ride...


...the differecnes are very real...you have only to be somwhat sensitve to the car and push it just a bit to note these diffences...one is at a disadvantage in some conditions with the 17" wheels and at an advantage in others...this car needs to be built up to a bigger wheel to gain anything further, imho....

...