I think I know the answer to this question, but I would like some opinions. The first picture shows the scratches in the rotor. If anything they look worse than in reality, but if you ran your finger nail across the rotor you would hear a near musical sound.

The second picture shows a apex seal grove. The other rotor has something like that with its apex seal groves, but not as bad. Notice how it sticks up and isn't even all the way across?

Thought?

 

From what I can see, yes. What's supposed to be wrong with it? Those grooves on the face are part of production...not all rotors had them, but some did. It affects nothing, even if the other rotor does not have the grooves.

 

Looks like there's some superficial rust in the groove - get all of that out.
Run an apex seal through and check for binding and proper clearances.
If all of that is kosher, just use it - go for it.


-Ted

 

that rotor looks just fine. do what Ted said then apply a light coat of vasoline to help prevent any rust forming.

 

Just to confirm, see this attached picture? The metal is pushed up/crunched a bit in the rotor grove. That is okay, correct?

Another question, I've put a straight edge along the rotor near the apex seal grove and it does not appear to be particularly straight. How much of a concern is that?

I didn't know that some rotors came with the rough lines. I've only ever seen smooth rotors.

Thanks for the responses, I had myself convinced that the rotor was garbage.

 

Looks like a candidate for 3mm seals to me. You may be able to save it. Get rid of any burrs you see and do what they said above, see if you get any binding and measure the clearances to see if they are within spec.

 

Yes, there is normally a lip that forms on one side of the slot, depending on which direction the rotor was spinning. This is where the top piece of the original 3pc seal was flexing and pushing against that edge and actually wore into it a bit. IF you look long-ways through the apex slot you'll notice the top is wider than the bottom. This is normal and not usually a concern, especially since seals are now 2pc and don't flex as much on top.

Just file down that extra material smooth and you're golden.

Surface rust matters not, btw. Anything in the grooves must be gotten out, but then you knew that anyway.