Coating on Z1 Rotors
 

Quick question, that maybe some people here can answer - or Z1 can chime in.

My track-only rotors are Z1 1 piece slotted blanks. They did great for me at the last HPDE, but the black coating on the hat and the outside of the rotor has melted a good bit. I first noticed this upon installing the rotors - brake cleaner makes the hats get "sticky" and the coating started to run off the rotors as a black/grey film, even prior to installing them.

I'm getting ready for another upcoming HPDE and have now noticed that the black coating must have softened at the track and formed ridges around the mating surfaces of the wheel. The rotors now present an uneven surface to the wheel. I will probably just sand this down so it's nice and smooth, but was wondering if anyone else has had a similar experience, and what the purpose of that coating is. I assume it's just for looks.

I can take pictures if y'all really want to see ;)


...of the rotors ;)

You probly overheated the rotors... (MAYBE)

But i'm sub'd to find out...:driving:

Image from Z1 showing the black coating on the center hat, and you can kind of see it around the circumference of the rotor. Note that I didn't get cross drilled:

http://www.z1motorsports.com/g37_370...600&page=popup

I thought this might be the case, but even before I installed them the coating started running off from brake cleaner.

Hmmm... I have the same rotors... I havent used any brake cleaner on them tho... But I have beat the ever living hell out of them... at AUTO-X

But I havent noticed the problems your having... My guess is has to be something with the brake cleaner... that or you did a way better job on beating the hell out of them then i did...

Interesting. I just used a different brake cleaner on them today, and I can dig my fingernail into the black paint.

On a related note, since the vanes aren't directional in the Z1 1 piece rotor which way are you guys running them? (IE, which way do the slots point).

Or if the vanes are directional and I missed that, maybe that explains everything haha.

Lol I would try and remove the coating before you use them again... I think it there for an anti-rust coating... And this is the way I have mine... (No clue if it right but it works an have had no issues...)
http://tapatalk.imageshack.com/v2/14...faa70bfb16.jpg


Sent from my iPhone using Tapatalk

If I were you I would try to strip all that crap off... And if you have to have the coating I would use a very high grit sand paper clean them up and use some very high temp paint... then have them turned and they should be like brand new...

That doesn't seem right. I would like to hear Z1's thoughts. But worse comes to worse, I think Wonka has the right idea. Strip all that crap off, prep and paint with hi-temp paint.

I read on their website under the 2 piece rotors that they have a special coating to resist oxidation. I guess this is the same stuff. I'm not too worried about a little rust, the rotors are cheap enough to just replace.

Per a friend who is a long-time mechanic:

Carb clean does melt the stuff off.

I've got the same rotors and have several track days on them with no issue.

Keep us posted.

Ok so then it was the brake cleaner... Thanks for the info brother...;)

you also asked about the direction of the rotor . if you look at the way the veins inside the rotor go they should pull air from the center outward . the outer slots direction vary from manufacture to manufacture . every performance rotor ive seen the leading edge of the inner vein should be forward . there made to draw air from the center outward . btw it deff sounds like the brake cleaner ate the coating . that kinda dissapoints me most manufactures use coatings that will not break down from using break clean ( considering that its BRAKE clean youd think they would use a better coating ) . if you clean that all off you can get a zink coating in a spray can . its what ive used in the past on rotors that had no coating to keep them from rusting . its like a grey ceramic color it dosnt look bad at all and if you get a little on them where the pads touch it cleans it right off as soon as you use the brakes . good luck brother .

But still, you should be able to use brake cleaner on your brakes without the finish melting off.

I totally agree!!! I want to know what Z1 has to say about this....

Thanks for the recommendation. On these specific rotors, the vanes are not directional. The only thing that is directional is the slots.

then its up to the manufacture . some prefer the pad sweep towards the center some prefer the sweep to the outer . you can probably look up what way they prefer them be installed . most manufactures mark the rotors l or r so there is no question . but given the issues with the coating and brake clean im guessing they dropped the ball in some aspects on these rotors .

Yeah, no marking on the box or on the rotors themselves. I just assumed they were pretty much non-directional and kinda more up to aesthetics.

The coating is strictly there to prevent rust and keep them looking cool. They will most definitely come off with even the slightest aggressive driving. And when it does come off it will rust, but its definitely not something you have to worry about. I dont think those rotors are directional. Im sure they are just blanks that have slots on them for aesthetic purposes.

Yeah, I hit them with some high temp paint to keep them from rusting. That being said, after track day #4 with these rotors they are developing tiny crack-lets so I may just switch to a higher quality rotor (one that I can also get resurfaced).