Rotor runout Options

[Olympic 914]

As one of my winter projects.

I had a slight pulsing in the brake, really only feel it just when coming to a stop. no noticeable pulling to either side.


So I hooked up the dial indicator to check the rotor runout. rears were .004 and .005
right front was .004 left front was .016

For what its worth I am running 911SC struts with A calipers. the rotors are separate from the hub. i did carefully torque the new rotors down to 18ft lbs in a star pattern when installing them.


Thinking I have found my Smoking Gun in a warped rotor, I ordered 2 new front rotors and new pads, although the old pads only had 16K on them and still looked very good. Figured new rotors get new pads.

So I get the left side back together today and was working on the right side, when I got the idea to check the runout.

Well wouldn't you know it the left side with a NEW rotor had .016 runout. WTF??

Right side back at .004, same as before.

any one have this kind of problem before?

the only thing I can think of is, when I installed the bearing races back when I first put them on, one of them wasn't seated all the way. or somehow got in there slightly crooked.

guess I will take it back apart and try to drive the races in further.

we shall see what happens.

[914sgofast2]

Your hub may be warped which is causing the runout. There is a YouTube Channel about this called "BrakeAlign" which discusses the problem. They used to sell special tapered shims to correct the problem, although they may now be out of business because their website is dormant/for sale. Maybe you can take the hub off and have a machine shop reface it so it is not warped.

I found that YouTube channel on Sunday afternoon because I was just looking for a "how to use a dial indicator" instructions.