Shimano rotors: anti-loosen plate?

micah356 · Apr 7, 2015

I just got a set of Shimano RT66 rotors. They came with these little metal plates.

All I can find on the internet is that they are "anti-loosen plates".

Here are some pictures I found of them:

Are they necessary? Do they make any difference?

7daysaweek · Apr 7, 2015

I've never used them or known anyone who has used them. Put on some new XT's a few weeks ago with the ice tech 6-bolt rotors and those went in the trash... Can't guarantee those bolts won't loosen without them but I have personally never had that issue.

micah356 · Apr 7, 2015

That's what I thought. But you can confirm that the second picture is the way they're meant to be installed?

I can't see why they would be necessary. This is my first time using Shimano rotors, but I've never had rotor bolts come loose before.

borabora · Apr 7, 2015

You'd think that Shimano includes these for a valid reason. They have the same function as a lock washer and act like a little spring between the screw head and the rotor. I doubt that you'd lose your rotor without them but why be a rebel in this particular instance? Weight savings?

Your picture looks correct

noapathy · Apr 8, 2015

Same reason they put that wire in with their adapters, lawyers primarily (and people who are not so good with tools). As long as there's enough thread lock on the bolts and they're properly torqued I've never had problems with them backing out. That being said, if they're easy to use, why not? 1% extra peace of mind

92gli · Apr 8, 2015

If you think those are necessary, I have some primo foil hats to sell you. A little loctite on the bolts is very sufficient. I've never ever encountered a loose bolt let alone all six.

Ronnie · Apr 10, 2015

I would contend that it makes absolutely no sense not to use them. There is no down side to including them. The bottom of the Shimano screw heads have a gnarled surface to mesh and lock with raised springs on the plates. You can hear them clicking as you tighten the bolts. they also act like washers. The gnarled surfaces are likely to score the surface of the disc and eat the metal away, especially on the likes of XT discs which have aluminum centers.

Shimano rotors: anti-loosen plate?

micah356

7daysaweek

micah356

borabora

noapathy

92gli

Ronnie

Top Contributors this Month

Recommended Communities