Measuring Runout

[Vinn]

Hi all,
From previous posts concerning replacing rotors, I've learned how important it is to measure for runout. However, I am unsure how to do this myself? Could someone please explain this procedure in detail? Thanks in advance.

Vince

 

[tom102]

Runout Measurement

I used a dial indicator with a magnetic mount, attached it to the caliper, zeroed it on on the rotor then turned the rotor by hand to check for runout (fluxuation), Hope this helps

 

[GerryLP]

Vince,

Like Tom102 said about the kits, these run-out kits are available everywhere. For checking on limit, however, take the total travel of the needle (whether its positive or negative).

Today, brake rotors are mostly trued while mounted on the spindle to account for small differences on the spindle alignment. I am told that these work pretty good.

 

[Jack]

As tom said.

You’ll need a dial indicator similar to this cheap one

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=33675

And a magnetic mounting base similar to this cheap one

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=5646

Firmly locate indicator & base independent of disk. Place the tip of indicator against face of disk. Rotate disk and observe variance on indicator … exert pressure as you turn so as to reveal any play in wheel bearings … you’ll see it as indicator needle bobbles back and forth. Not much detail but it works.

-edit- I have a pair similar to above. I use em for all sorts of stuff ... including degreeing in cams and indexing bellhousings.

JACK:gap

 

[Vinn]

Thanks everyone!
I think I'm ready to get this job finished now.

Vince