how to run smaller diameter rotors. machine calipers/spindle or just run em?

brake caliper and spindles call for 310mm

bike normally uses 298mm rotors.

what happens if i run the 298mm rotors as is? chatter?

i'm not really interested in running the larger rotors. i would like to either run them as is, or machine the difference off either the caliper, spindle, or both, to bring the radial caliper in the 6mm to run 298mm rotors.

 

If you run smaller rotors than the calipers are set up for, you won’t have full braking power as your pads won’t have full coverage on the rotor surface. If you don’t want to run the larger rotors, then you need to do the machining to get everything in proper engagement.

 

What's the reason to not run the larger rotor? Seems like a lot of hassle to go backward.

 

The other issue with running smaller rotors is you'll wear lips into the pads. If ignored those lips will bind the pads before you wear them out normally.

 

i'm going to machine the spindles and the calipers to space the caliper as needed to run the 298mm rotors.

thanks guys.

the bike already has plenty of stopping power as is, so i would like to keep the lighter rotors.

 

Try to take it all off the caliper. Don't take any off the stanchion if you can help it. If you lose that contact area on the stanchion you lose the strength of that attachment point. You will also probably have to remove the stanchion/foot from the fork leg to machine it, PITA without the proper tools.

 

Braketech Ceramic Matrix Composite rotors.

 

I think we all are assuming this is a radial setup? Not to question your intelligence but remember that rotors are measured in diameter, you are worried about radius distance so if it's 12mm small remove 6mm from whatever it is you choose.

 

Yes, it's a radial setup.

the braketech CMC's would be a wonderful choice if they were actually available. I am looking at braketech axis irons, using a V4 carrier with a 298mm disc mated up to it, with custom machined hub centric spacer to make up for the difference in size on the hub of the front wheel on the 250.

 

If you can cut all from calipers. I cut good number of R6 calipers for this same reason

 

Yup.
BTW, I love my AXIS/Irons. Butter smooth, prolly due to the solid rotor design. Night and day improvement over OEM on my CBR. Going on my second set, gonna be the semi-narrow band this time around.

 

Hello,

I machined my calipers 6mm to properly fit the rotors.

Thank you for the information and help.