vibration while braking? (Not vibrating anymore, but now what?!!)

[REDUC]

A friend pointed this out after riding my bike.  I hadn't noticed before he mentioned it.  It's pretty subtle, but I did notice it today on a ride around town.  It almost feels as if the caliper is rapidly gripping then releasing the disk.  Almost pulsating.  I can especially feel it when coming to a complete stop.  Any ideas?  Are my rotors warped?

[darthmoto]

Thats what it sounds like.. were the rotor bolts torqued down all equally thru 2 stages and in a star pattern?

EDIT: Heh.. nevermind my post... Previous bike being an old Honda Hawk, I forget that new rotors have floating discs.. 

[Langanobob]

This article is worth reading:

http://www.stoptech.com/tech_info/wp_warped_brakedisk.shtml

[Howie]

Clean the discs with brake cleaner and a Scotchbright pad.  Also make sure the buttons that hold the rotor blade to the carrier are free.  Remove the brake pads and sand them.  While you are at it, chamfer the leading edge.  Pray to the motorcycle gods.  Now go out on the road and bed them in.

[Dave]

Have you replaced the pads recently? Could be something as simple as glazed pads. As said earlier give the pads a sand.

[Norm]

My guess would be warped or hot spots. As stated though, clean everything - don't forget the cups that activate the pads thenselves. Clean with q-tip and brake fluid.

[REDUC]

Thanks for the information.  I'll check it out.   

[RUFKM]

I had the exact same problem.  Before you go over the edge just simply clean the rotors with a green scotchbright & dish soap.  It's amazing how much junk comes off of a "clean" looking rotor.  One cleaning totally solved the problem for me.  Now I do it everytime I wash the bike.

[REDUC]

Thanks for the info.  I only just today got around to looking at my bike.  I don't know what glazed pads look like, and maybe you guys can tell from my crappy photos, but the pads could use some replacement anyway (wear grooves no more!)  I ordered up a EBC HH Front brake pad set from CA Cycleworks, and will give the rotors and calipers a good cleaning.  My bike was a demo when I bought it, so I doubt the brakes were ever properly bedded in, although they were, and still are really stout.

[Norm]

Hey - send those to me, I'd get another 10,000 miles from them!!!
To clean surfaces, I touch the pads on a belt sander and hit the rotors with a ball rotor on a drill. I've also used a 2" angle sander with a scotch type pad. I don't think you'll knock down much by hand, those things are pretty tough. If you do any of the above, you'll need to rebed the pads.

[RUFKM]

Looks like your throwin' away new pads.

[ducatiz]

Remove the brake pads and sand them.  While you are at it, chamfer the leading edge.  Pray to the motorcycle gods.  Now go out on the road and bed them in.

Hey - send those to me, I'd get another 10,000 miles from them!!!
To clean surfaces, I touch the pads on a belt sander and hit the rotors with a ball rotor on a drill. I've also used a 2" angle sander with a scotch type pad. I don't think you'll knock down much by hand, those things are pretty tough. If you do any of the above, you'll need to rebed the pads.

I use a cheap-ass hand held orbital sander with a fine grit paper.  Usually takes about 2-5 seconds to get a new surface. 

I do it in the driveway.  Press HARD with the sander and turn it on.  You just need to make sure the pad doesn't move around.  Smooth concrete will hold the pad nicely. 

Use the same pad and chamfer the leading edge as Howie suggested, but then do the whole pad again so there is no lip.  You want a tiny chamfer. 

Make sure to install them with the chamfer facing against the rotation.

[REDUC]

  So, at what point should I replace the pads?  These have about 4mm of material left.  The manual says to replace when the wear grooves are gone, but frankly, I don't remember there being any grooves...

[ducatiz]

So, at what point should I replace the pads?  These have about 4mm of material left.  The manual says to replace when the wear grooves are gone, but frankly, I don't remember there being any grooves...

4mm is a lot of material.  i would not replace them.  put the new ones aside and ride for another 8-10k miles on them.

[REDUC]

Thanks, I'll do that.