Brakes

[VIJAYSM3]

Anyone had issues with brakes ? Does not seem powerful enough .. coming from an M5 so that might just be something relative, but not sure if anyone else has had similar issues .. thanks !

[VGM6]

Considering the car weighs about 1000 lbs more that could be why. Ive seen people upgrade to 6 piston front and 4 piston rear brembos but your looking at probably spending another 7-8k and from what I've heard they won't fit the stock or winter 20's but should be fine with 21's. Cheers

[Alextacy]

The brakes aren't as impressive as the acceleration and handling that's for sure, but I do think a bit of it is in the brake feel. Different pad choice may improve things somewhat, something more aggressive. The stock units seem to be very low wearing/durable units, so a softer performance pad could help out. Making sure theyre bed in correctly too. Definitely cheaper than a bigger break kit.

[r33_RGSport]

I notice that the brake came brand new in the car is not fully bedded.
I managed to bed one of my customer's car stock brakes, and it felt much better.
As far as softer pad, be careful on what you wish for. Softer pad or more sticky pad, usually make noise.
Upgrading to Brembo 6 piston front and 4 piston rear will be much better.

[WCH]

It's a lot heavier vehicle than the M5.

[gblansten]

C&D has my 14 M5 stopping with standard brakes 70-0 in 165 feet and the 15 X5M stopping 70-0 in 152 feet. Not sure what the problem is.

Edmunds has the M5 at 111 feet versus 104 for the X5M for 60-0.

[gblansten]

M4 with CERAMIC brakes 70-0 is 151 feet.

[onfireX5]

Those numbers are killer for the X5M. Impressive.

[paliknight]

Originally Posted by gblansten

M4 with CERAMIC brakes 70-0 is 151 feet.

Probably because at that point the tires are far more important than the brakes. Once the brakes stop the tires from spinning, it doesnt matter what size brake kit you have on.

[gblansten]

Originally Posted by paliknight

Probably because at that point the tires are far more important than the brakes. Once the brakes stop the tires from spinning, it doesnt matter what size brake kit you have on.

Agreed. Just wanted to make it clear which brakes were used in that test because it would probably come up.

[NikonMan]

A stock 911 Turbo S (~3600 pounds) stops 70-0 in 144 feet vs a stock X5M (~5260 pounds) 70-0 in 152 feet - 8 feet longer with ~1600 pounds more weight.

[paliknight]

Originally Posted by gblansten

Agreed. Just wanted to make it clear which brakes were used in that test because it would probably come up.

No thats understandable. for the F80/F82/F83 the difference in braking power between the regular setup and the CCBs is only noticeable on the track since the CCBs handle more stress and dont fade as the regular ones do.

[gblansten]

Originally Posted by paliknight

No thats understandable. for the F80/F82/F83 the difference in braking power between the regular setup and the CCBs is only noticeable on the track since the CCBs handle more stress and dont fade as the regular ones do.

Yep. It's all about fade resistance.

[r33_RGSport]

Don't forget proper bedding.
Good stuff if not setup properly will not function as designed.

[RPI-M5]

I was having this exact same thought. The braking issue is more noticeable with the winters hat have less tire on the rear.

One thing I can't help but think is part of it is the single piston rear calipers. One thing I'm going to do is go with stainless brake lines.

There may also be some truth to the stock pads being too passive. If you check on iDrive it shows service interval for the pads at something like 35k or more.

[VIJAYSM3]

Originally Posted by RPI-X5

I was having this exact same thought. The braking issue is more noticeable with the winters hat have less tire on the rear.

One thing I can't help but think is part of it is the single piston rear calipers. One thing I'm going to do is go with stainless brake lines.

There may also be some truth to the stock pads being too passive. If you check on iDrive it shows service interval for the pads at something like 35k or more.

Do you guys think I should take it to a dealer and get it checked ? Have them check my pads and rotates .. since it makes no sense with some of the numbers I see that it comes to a stop better than the m5 but sure doesn't seem to .

[ajob]

I would just stop worrying about the current stock X5 M brakes - they are very good and way overdesigned for even German Autobahn's repeated 130 mph start/stop traffic and you may notice some fading only after quite a few high speed laps on some "curvy" tracks, but unlikely to ever happen on street driving.

60 mph stopping distance depends from our tires, not our brakes -- and, maybe, also a little from the ABS settings, which look to me a little on the conservative side -- to keep furious truck driving grannies safe?

[TonySCV]

Agree with others that the "bite" of the brakes will improve with proper bedding in. If you feather it for stops over and over and over again, it won't feel as though the brakes are as effective as they actually are.

[infamousdiz]

the cold brakes have no bite but once you get some heat in them its good. 6 piston vs 4 piston doesn't matter if the 4 pistons are larger then the 6.