Rear Brake Hanging Pic

[rboe]

No heat, just elbow grease.

[White Dog_imp]

That is because it got heated up and warped while riding. When it cups like you see in my picture it starts to wear against the caliper body. They don't come warped from the factory. If it did you would have noticed the poor slow speed coasting, like moving it out of the garage etc. The dealer should have noted it while moving it around the dealership, like off the crate. Very poor form on their part if it came that way and they didn't catch it. They are selling, but I'm not buying. Moot point since it will be covered.

If you got a chance to look at the back side I'm pretty sure you'd see the discoloration. I was not able to inspect the back side of the first disc, just the out board side and the edge (both edges toasted the black paint off into a white ash).

Interesting. So I should expect to see warping on my rotor when it is removed. That may not happen as I gather the shop will have to send the rotor back to Honda as a damaged part in order to get paid. Makes me wonder how my rotor got grooved so quickly.

Interesting. So I should expect to see warping on my rotor when it is removed. That may not happen as I gather the shop will have to send the rotor back to Honda as a damaged part in order to get paid. Makes me wonder how my rotor got grooved so quickly.
Update: I didn't get to see the rotor but another CB1100 owner said he watched the mechanic R/R the rotor and he said mine was definitely warped. After I measured the distance between the new rotor and the caliper, I got .050" clearance so the old rotor must have really been warped badly. Cheap metal, maybe?

[rboe]

Not cheap, but if you will refer back to my pictures you'll see that the disc is ground flat on one side (the inside surface) but the side you see on the outside surface is raised above the plane that the bolts attach to. Looking at it edge wise, it is not symmetrical. THAT, I think is what warps it (at least contributes to it). I suspect, but have no proof, that one of the disc pads sees more pressure (and hence develops more heat) so maybe the assymmetrical heat production causes or contributes to the warping.

My Quota discs were flat on both sides and warped. Big thick car rotors will/can warp. So, "big shoulder shrug", not sure just what the heck is going on! Other than heat is bad.

[White Dog_imp]

When I got home yesterday from the Honda shop, I touched the rotor to see how hot it was. (I had not used the rear brake and kept my feet on my highway pegs.) The rotor was warm to the touch but not hot. The warmness was caused by the brake pads rubbing slightly, as I guess they are designed to do.

[rboe]

I think the paint can take the heat from normal use (which can get pretty warm, after all you are taking rotating inertia and converting it to heat and sound), but riding brakes - the difference being how long the pads are pressed into the disc, not so much by how much pressure. A panic stop will heat it up pretty good but only for a very short duration so it should be good.

Remember those old ads on TV where they have a pickup going down hill and they are hosing the brakes down but good with water to show how well they work? The thing is, pouring water on them while abusing the brakes going down hill would be the best thing you could do. That water is going to take a lot of heat away from the brakes.