I bought rebuilt 30mm aluminum Z32 calipers and Z32 rotors to replace my current setup. I needed new calipers and rotors so I decided to just go with Z32 calipers. Later when I can afford larger winter/track wheels, Ill go with bigger rotors.

My question is, I know most people mill the rotors down 4mm but I have read a few people grinded down the inner caliper instead to make the rotor clear. I tried searching for the posts but couldnt come up with anything. Any opinions about this? I would rather do it this way because I could do it myself and I dont have to pay someone to mill the rotors and if I have to replace the rotors I dont have to worry about milling them.

 

Usually you don't want to remove material from the caliper.

 

mill the rotors. grinding the caliper is not safe. The only caliper grinding anyone has done was for the thickness of the rotor, not the diameter.

 

Ill just go with milling the rotor, I just have a feeling the machine shop is going to charge me way too much for it. Thanks.

 

The shop charged me $60 to machine my Z32 rotors.

 

I went to the local machine shop and they wanted $130 for 2 rotors
Im going to try some other places tomarrow.

Anyone do it themselves? I was thinking about bolting them to the hub and taking an angle grinder to them while spinning. Dont know if that would be a bad idea.

 

It would be a very bad idea. You will never remove the same amount of material all the way around the rotor and it could possibly destroy other components in the process of not being balanced while spinning. Besides, it would take forever to remove 4mm of material with a grinder.

 

Yea, I was thinking it would be difficult to get even, just trying to avoid paying $130.

 

The shop that did my reverse y-pipe and downpipe was able to do it on a Lathe and it cost me $50.