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Rear Brake Rotor 2009RT damaged

tgf429

Plasterman
OK, not the smartest thing I've done but my rear pads on my 2009RT have worn down to the metal and have made some minor grooves in the rear rotor. Do I need to replace it, can it be turned on a lathe or should I just replace the pads and call it good?

Never thought the pads would be shot a 15000 miles and was not paying close enough attention:banghead

If I was to replace the rotor, is there an aftermarket rotor that is an improvement from the factory rotor?

What are good pads to use for replacement both front and rear?



Thanks


Tom
 
You got within the range of what happens to the rear pads.

However, do remember that the inside pad is thinner than the outside pad on the rear BY DESIGN. You either need to pay attention to those rings on the pin, look at the inside pad directly, or learn to inspect the inside pad through the little inspection hole in the caliper and pad (only works with stock pads, aftermarket brands don't have a hole drilled to inspection depth on the inside pad material).

I use EBC HH but they don't last longer. Use them for a slightly more solid feel- which might tempt you to use rear more and actually decrease pad life. Many dealers sell and recommend the EBC HH pads front and rear.

I'm always leery of non stock rotors but they do exist. I suppose if you EBC pads an EBC rotor ought to work well with them. There re others but surface finisih sometimes has a bearing on how well new pads break in.

Re rotor grooves- if not very deep, just use as is. You cannot turn a bike rotor- you will below the thickness limit almost certainly- the spec only allows 0.5 mm of wear IIRC.
 
Examine the rotor. It is OK to ignore the grooves (for now at least). But you need to remove any high spots (globs) that will just chew up the pads. I had to do this while on the road one time and used a knife sharpening carborundum stone about 2" x 5" in size. On the centerstand, bike idling briefly, in gear with the flat stone against the side of the disk. Not in the manual but OK as a good stop-gap measure.
 
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Agree totally with Paul. It's just not worth replacing the rotor for a small bit of contact, but smooth it out a little.
 
And to answer your question on aftermarket, I've had good luck with EBC rotors. They're better than stock because they're 1/2 the price.

When installing them - I'd suggest getting new screws. They have loctite on them (blue).. and are generally considered a one-time use item. Also you'll need a T40 driver. You need one with a long shaft. There is a divot out of the bottom of the rear drive (at about 7PM looking at it from the port side of the bike) that is used to access the screws. If you have a short driver - it won't fit into the divot squarely and will booger (tech term) up the torx recess in the screws. It's important to make certain the mounting surfaces on the wheel flange are CLEAN and smooth, and to progressively torque the screws down using a criss-cross pattern. I forget what the torque spec is, but it's fairly low.. If you can't find it - ping me and I'll dig it out for you. DO use a torque-wrench.
 
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