When to replace Rotors?

[CrazyMedic]

I am slowly getting my build done, but the bike is still in the shop (damn five weeks now!?!). I am looking at getting the wheels powdercoated and wanted to do something with the rotors, paint ect. I have the idea of replacing the rotors, pads, a NEW master cylinder, rebuild the rear master cylinder, and SS brake lines. All nice stuff right. However rotors are $160 a rotor, WTF?!? So I might keep mine if they are in good shape, but how do you check? Do you mike them like car rotors? Anything that I need to do if I keep the rotors and do new pads? Ok thanks for the help! Hopefully will have the bike done by christmas!
Nik

[The CyberPoet]

The rotors have a minimum-thickness limit as the basis for replacement. I don't know what that minimum thickness is for an '88, but I would guess it would be about 85% of the original ("new" rotor) thickness. There is also a run-out check, but motorcycle rotors rarely get warped under normal circumstances. MC rotors also do not normally get resurfaced (milled) the way many car rotors can be, because the machinery to do it is very rare and the minimum thickness level is usually too close to make it worthwhile.

Cheers
=-= The CyberPoet

[BraadaJim]

I believe the minimum thickness is 4mm.

[CrazyMedic]

I am going to paint the center section where the bolts are, thats it- make it bling bling
Nik

[md86]

I BELIEVE the min. thickness is actually on the disc somewhere ....

[The CyberPoet]

any one seen any bikes with painted calipers?

Several people around here painted theirs and posted up about it... See

VHT Caliper Paint (Speedee):

http://www.katriders.com/forums/viewtopic.php?t=4262

DupliColor brand caliper brush-on paints (BadKitty):

http://www.katriders.com/forums/viewtopic.php?t=6060

Cheers
=-= The CyberPoet