So I recently changed my rear rotors/pads and immediately discovered that the pad doesn't cover the entire rotor face. The problem is that 2 days after I installed them I washed the car and the portion of the rotor not swiped by the pad turned to rust. I had purchased the premium rotors partly due to the "e coating" in the hope that I wouldn't have to paint the rotors at least for a while. When I emailed R1 about this they said that this was normal and a "trick" that G and Z owners do is to paint the rotors before installing them. I find this to be ridiculous. Clearly the rotor wasn't made with the Z solely in mind. I searched and didn't see anything regarding this and to be honest I was surprised I didn't find anything. Has anybody else run in to this problem?

 

That's how rotors work. Spray them like they suggested, or deal with only the rubbed area remaining shiny. You haven't been ripped off or sold an inferior product.

 

Simple solution. The slots aren't coated..so simply spray high temp (black ...or silver if you don't want slots to be high lighted) paint over the surface surrounding each slot..not the entire rotor surface. Do 2 coats (you can do this on the car). Take it out and hit the brakes...swept surface will be stripped of excess paint with inner slots painted. Done...no more source of rust.

 

next time go Brembo

 

Power Slot (Centric Premium Slotted) rotors are coated AFTER slotting. I have no rust in my slots.

 

It doesn't sound like OP is complaining about the slots, but he's complaining that his brake pad doesn't scrape the whole face of the rotor all the way to the point where the factory coating starts.

 

Hmm I do. Just installed mine last week. Lots of rust after rain, not very happy about it.

 

That's certainly not how rotors work. Had the rotor been designed solely for the Z the rotor face would only be as wide as the pad going over it.

Exactly. The picture is from right after I installed them but after washing the car there is a .75" rust ring around the inner portion of the rotor.

 

Not on my z but on my TL I had stop tech rotors and same thing happens. I am not for or against your rotor brand but it sounds normal to me. My shop told me to paint mine around the hub area so that it wouldn't show but never got around to it.

 

Wrong answer NOOB. It might be wise to just read for awhile before posting.

 

Ha! So are you trying to tell me your OE rotor face is .75" wider than it needs to be? I've been on this forum over 2 years longer than you so maybe you should just read past a post count.

 

He's right..you're wrong.

 

Yes...I was just looking at slots as source of rust...but pads will not reach all the way with these. If the surface is properly coated, the unswept area won't rust and it *looks* to me that this area is coated and not producing rust. If not..like mine..you need to paint either paint surface and let the pads clean it up..or only paint the unswept area and masked off the rest (I did this).

 

Love to hear how I'm wrong because this is how they should be...





In the first picture you can see where the calipers/pads had swiped the rotor from end to end of the slots. The second picture shows how some company's cheap rotors for the back of a Z even got it right. In my picture you can clearly see that the pads don't even come close to accomplishing this. R1's premium rotors (Centric premium) inner "diamond tip" wear indicator is negated by the fact that the pad will never even touch it. If they were designed with only the Z/G rear calipers/pads in mind R1's rotors would have come with shorter slots and their "e coating" would extend to the used portion of the rotor face.

I think its ridiculous that their premium rotor has such a poor fitment and despite their "e coating" needs to be painted right out of the box to prevent a large unsightly rust ring from forming. I'm just trying to see if anyone else has this issue with their R1 rotors or if they recently changed the way they were machined because, as I had said, I'm surprised I didn't find any complaints.

 

Could it be that OP bought the rotors for Brembo-equipped Z? It looks like the rotor is too big for the caliper. I'm not sure.

 

No. The Brembo rotors are a larger diameter and wouldn't allow the standard caliper to be mounted. The issue is that the surface area on this R1 rotor extends inward toward the center of the rotor more than necessary and there is a good portion left untouched by the pad.

 

The rust ring is normal on lower-quality rotors and should be expected unless you go with a rotor that specifically states it is zinc coated or not otherwise prone to rust. I've seen cheap Chinese Autozone rotors turn to rust 30 minutes after spraying off the protective grease coat they come shipped with. My experience with the Centric Cryos have been good. Powerslots are OK, but they warp way too soon. I haven't used the R1s, but their response about painting the non-contact surface area really is a bit of a joke. If they were "premium" they would have electrolytically plated the rotor with zinc so that as the rest of the rotor wears and the ferrous metal is exposed, the original surface area that is not in contact with the pad (i.e., the plated surface) would stay rust-free.

 

Thought I'd post a picture so its very clear to everyone what I'm talking about. This rust ring is after one wash and shouldn't be considered normal..

 

i used R1 on my Brembo equipped Z for 2 years with no issue.

 

meh. costs savings for the company to sell one product instead of making two. paint it, get over it. buy napa or rockauto blanks next time and save urself some $.