[Onizukachan]

Personally I liked the dustier of the two msport pads on the street. Good pedal feel amd initial bite an d quietness. Others don’t like the wheel cleaning every week or so amd so make other choices.

[casualDIYer]

Originally Posted by TK335iMSPT

Rotors-
The Zimmerman rotors felt like the same weight as OEM. The only different I noticed were the OEM rotors caps seemed to have rivets on them where as the Zimmerman’s appeared to be a single cast. I am not sure what difference this makes. The Zimmerman Rotors are also Zinc plated, I will monitor the amount of corrosion that forms on the hats as this is a known issue with the OEM rotors.

If you do not see the rivets, that is because you bought 1-piece rotors. Zimmerman does sell 2-piece rotors, with the difference being the 'hat' part of the rotor is typically made of aluminium. This saves a bit of weight and will not 'rust' in the sense there is no orange-red crust forming. Aluminium tends to 'grey' over time, which you can polish to restore shine.

Another alternative is the 'floating' rotor, in which the disk is (sometimes) bolted to the hat. In the case of 'bolted' models, one can replace the disk on a regular basis, reusing the hat. BMW does make a floating rotor but I've never seen the use of bolts. Floating rotors look really cool but it's their $1000+ a pair price makes even most enthusiasts pass on the option, at least for the F30. If one has an M3, well, you've already got poor impulse control when it comes to fast cars and money so what's another grand?

[casualDIYer]

Originally Posted by ssjelf

Mine clack when switching from reverse to forward and vice versa. Also sometimes when I apply the brakes after coasting. Do you get that on yours? Mine are in the m performance calipers if it makes a difference.

The 'clack' is the result of the piston striking the back of the pad.

When new, a full pad will consume almost all the space between the piston and the rotor. But as the pad is used, a gap will start to form between the piston and the backing plate because the pad, held in place by the pad pins, but not attached to the piston (unlike single caliper brake pads), will only retreat a small amount compared to the piston. On next application of the brake, the piston will 'clack' against the baking plate.

Buying new pads when the sounds starts to bug you is one way to fix the problem. Alternatively, buy shims for your Brembo caliper made of stainless steel or titanium but given that for anyone to make a living do that, they'd need to charge a $100 for a set of 4, so you're getting close to buying a new set of pads.

[casualDIYer]

Originally Posted by Emerson335

For what it’s worth…I’ve put 1,000 miles on my new Hawk 5.0 pads over the past 2 weeks and have zero squealing or noise. Like I shared in my previous post, my Hawk pads did not include weights, and I also chose not to apply any pad grease. I’m running regular (flat face) Zimmerman rotors that are a little over a year old. My driving has been a good mix of short local trips to triple digit highway speeds, as well as both wet and dry conditions. I’m very happy with the pads so far, good feel and no noise, so I appreciate the recommendations from others here on the forums.

This is kind of an interesting experiment "no application of pad grease". Grease, the lubricant, not movie starting John Travolta, keeps things moving but it has a downside whereby it's stickiness attracts dirt and dust. Disintegrating brake pad = a lot of dust. I wonder about a few ideas here:

1) Lubrication. Would there be additional heat build up on the pad if it cannot slide away from the rotor when the brake is released. Would it prematurely wear the pad? Would it heat the pad (or prevent it from cooling) thus transferring more heat to the caliper? Could the caliper suffer greater wear? Finally, would the rotor wear quicker?

2) Corrosion resistance. Since 2 and 4 piston calipers on BMWs are made of aluminium, I can't see the pad fusing to the caliper, unlike the case of 1 piston calipers, where pads 'ears' fuse to the pad carrier due to rust. In general, pad material life tends to be shorter than backing plate life, but would an increase in corrosive action due to a lack of grease make a difference?

These might be elements you want to check on. BMW does instruct repair techs to use grease. I would not go against this advice but I wonder how little one could get away with? I certainly use a lot less now than in the past with no ill-effect.

[WDE82]

Originally Posted by casualDIYer

This is kind of an interesting experiment "no application of pad grease". Grease, the lubricant, not movie starting John Travolta, keeps things moving but it has a downside whereby it's stickiness attracts dirt and dust. Disintegrating brake pad = a lot of dust. I wonder about a few ideas here:

1) Lubrication. Would there be additional heat build up on the pad if it cannot slide away from the rotor when the brake is released. Would it prematurely wear the pad? Would it heat the pad (or prevent it from cooling) thus transferring more heat to the caliper? Could the caliper suffer greater wear? Finally, would the rotor wear quicker?

2) Corrosion resistance. Since 2 and 4 piston calipers on BMWs are made of aluminium, I can't see the pad fusing to the caliper, unlike the case of 1 piston calipers, where pads 'ears' fuse to the pad carrier due to rust. In general, pad material life tends to be shorter than backing plate life, but would an increase in corrosive action due to a lack of grease make a difference?

These might be elements you want to check on. BMW does instruct repair techs to use grease. I would not go against this advice but I wonder how little one could get away with? I certainly use a lot less now than in the past with no ill-effect.

None of those things are really much of a concern with going greaseless. The grease is pretty much just for squealing.