[bmwexecutive]

Just came back from bedding in my brakes per the guide on Zeckhaunsen Racing's website. Actually went to a spot by an elementary school, a short straight away near my house first to see if I could use that spot since there's no traffic on it on the weekends and I got up to about 50MPH, went over a fairly large "hill" in the road that puts me higher up on the other side (not like a speedbump where you go up and down, this one just went up) and I must have gotten at least an inch of air. I swear the entire car was literally flying for a second and that was fun, the coming down and suspension compressing part, not so fun. Haha. Luckily, as far as I can see everything was OK, did a full exterior top and bottom check and seems I got away unscathed. I figure that's the kind of stuff BMW puts their cars through on the Nürburgring so I didn't worry too much. Just figured I better do it on the longer, flat, road.

So to what happened: Did my 8 near complete stops from 60MPH to 10MPH---road was only long enough for 4 each way so I had to turn around. Then I cruised in laps around the parking lot of the elementary school applying literally almost no braking power whatsoever for 20 minutes so the brakes could cool. The one time I did very lightly use the brakes for a moment I definetly felt the brake fade. It was unmistakbly noticable.

In any event, I'm back home now after letting the brakes cool by cruising for 20 minutes (hopefully that was enough) and I took pictures of the brake rotors. Just want to make sure this is how they are suppose to look---you know how I am, nervous about almost everything that comes to my car.

*They're big pictures so that you can get a good look at the rotors----also first two is the same wheel rotor, last one is a different wheel*

[bmwexecutive]

Ummm, I think I'm confused. Here's what ///Matt said about these pictures "I think you may have overdone it a little, bud. Blue on the rotors is a sign of overheating them, which in turn hardens them, and makes them less efficient."

But Zeckhausen Racing's directions specifically say (here: http://www.zeckhausen.com/bedding_in_brakes.htm): "After the break-in cycle, there should be a slight blue tint and a light gray film on the rotor face. The blue tint tells you the rotor has reached break-in temperature and the gray film is pad material starting to transfer onto the rotor face. This is what you are looking for. The best braking occurs when there is an even layer of of pad material deposited across the face of the rotors."

[ward]

if they're not squealing when you stop, or vibrating when you stop

you broke them in correctly. As far as I know you can't tell much by looking.


poorly bedded in brakes exhibit lots of excess brake noise

[MonacoBimm]

My brakes sqeal a lot after maybe an hour of using the car. And the squaling noise, when coming to a stop is not a contstant squeal its like every wheel squals at its own pace.

[bmwexecutive]

Originally Posted by ward

if they're not squealing when you stop, or vibrating when you stop

you broke them in correctly. As far as I know you can't tell much by looking.


poorly bedded in brakes exhibit lots of excess brake noise

No squealing what so ever---just took it for a gentle cruise around the neighborhood. There is light vibration right before I come to a complete stop, although, that's been there ever since I got the car so it hasn't changed with my bedding in the brakes today. I hope doing that was going to get rid of the light vibration---it's nothing serious though.

Far as I can tell the brake performance is the same. And I was told by bedding in the brakes the brake pedal would get firmer. I'm pretty sure it didn't get firmer, it got softer. What does that mean?

[ward]

pedal firmness doesn't have anything to do with bed in procedures, that has to do with fluid type and freshness mainly.


I'm sure you're OK here.

[boyce'06 330i]

They look just like mine, but I doubt you can tell anything by looking. The
Zeckhausen site clearly says they should have a bluish tint to them, and as long as you don't feel any abnormal vibrations, or see any cracks in the rotors you should be fine.

That's the nice thing about brakes... if they had gotten damaged during the process you'd definitely know it.

[bmwexecutive]

Originally Posted by ward

pedal firmness doesn't have anything to do with bed in procedures, that has to do with fluid type and freshness mainly.


I'm sure you're OK here.

So what purpose does bedding in the brakes serve then? In the 2 miles I drove I didn't notice any difference in stopping power?

Also,by fluid type and freshness do you mean bleeding the brakes? How much would that cost to get down at a BMW dealership? I only have 3300 miles on my car but I'd probably be willing to pay a couple hundred bucks for a firmer brake pedal. It's much firmer than say my mom's Lexus GX470 now, but I like a real firm brake pedal.

Also, so you're sure there is no difference in my brake pedal firmness since bedding in the brakes? It feels like it's a little softer but I'm not 100% on that.

Thanks for all your help!

[bmwexecutive]

Originally Posted by boyce'06 330i

That's the nice thing about brakes... if they had gotten damaged during the process you'd definitely know it.

Really? So it would be really noticable then if someone was wrong? They seem to perform just as though they did before bedding them in?

[bmwexecutive]

Also, isn't is abnormal to have part of the rotor light gray and the rest dark gray like seen in the first and second picture? I think that's what is worrying me the most.

[ward]

bedding in, the process is just to help the new pads, and new rotors get to know each other gently so that they don't warp or make crazy noises when you use them.

it's just taking a bit of time to make sure they surfaces conform to each other and prevents brake noise later down the road.

a fluid flush probably isn't needed, (2 years in the factory spec/I'd wait and get it for free later)

[bmwexecutive]

Originally Posted by ward

bedding in, the process is just to help the new pads, and new rotors get to know each other gently so that they don't warp or make crazy noises when you use them.

it's just taking a bit of time to make sure they surfaces conform to each other and prevents brake noise later down the road.

a fluid flush probably isn't needed, (2 years in the factory spec/I'd wait and get it for free later)

Gotcha. Is a fluid flush the same as bleeding the brakes? Also, are you saying every 2 years BMW offers a fluid flush for free under the warranty? I'm only going to have my 330i for another 6 or 7 months so I might as well pay for a fluid flush now assuming it will give me a firmer pedal.

[shimshimhada]

I doubt you will feel a noticeable gain in pedal firmness if you bleed your brakes right now.

Bedding your brakes offer a couple of benefits including extended pad life, increased braking power, and reduction/elimination of brake squeal.

Obviously, in daily driving, you won't notice any increase in bite, you'd have to take your car to the track to feel any difference.

[bmwexecutive]

Thanks for the info, guys. To be honest, I really wish I never messed with bedding in my brakes in the first place. My rotors have a blue tint to them now (I thought that's suppose to go away?) and I don't get anything out of it. I put my car through hell and there's really no advantage to it. But I guess what's done is done.

By the way, if at some point in the future I have to use ABS, isn't that going to mess up the even layer of brake pad material on my brake rotors because the ABS locks and releases, locks and releases?

[bmwexecutive]

Also, probably a dumb question, but I can go out and drive my car and use the brakes just as hard as I was doing before bed-in, right? I think it's the physiological thing of seeing the blue tint on the rotors that makes my brain think the rotors haven't cooled down yet (even though it's been about 20 hours since I did the bed-in) and I should go easy on them.

[longtran]

hey bmwexecutive, i see brake dust on your wheels. better wipe them off. or you werent so anal as i thought you were.

[hemi to e90]

i like ward

hes smart!

[bmwexecutive]

OK, it's official: I took a nice long drive today and had some time to test out my brakes and they indeed work better than they did before. It's pretty noticeable too. Glad I broke them in correctly. And every other time I inch forward at a stop light in traffic I can do it without any grabbing noise or vibration whatsoever, as opposed to before bedding in the brakes when I always had just the slightest grabbing noise when inching forward. The biggest difference though is when I'm coming to a turn, slowly apply pressure to the brake pedal and then apply stronger pressure---that's where I notice the difference with very noticable stronger braking power. I have to say that I'm impressed that this worked. Thanks for keeping me thinking positive Ward!