Is a polydrive or a Ribe drive used for the rear brake calipers? The PMB video says to use an R5 Ribe, but states you can use a T27 Torx, but it is better to use the Ribe. When looking for a Ribe bit, I cam across the Polydrive. There seems to be some confusion as to what, specifically, is needed. Anyone have a definite answer for the 914 rear brake calipers?

Here's a picture:
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I used the ribe

I second Brant, the originals are Ribe. Where the Ribe head bolt is used with a nut, then always turn the nut while holding the bolt from turning with the tool. This will save you from breaking as many Ribe bits as possible.

Ribe all the way

It's a Ribe bolt so...

Thanks to all. I bought a Ribe bit, so we'll see how it goes.

I was looking at some ‘RIBE’ bits on Amazon, and the description also referred to them as polydrive. I posted a question, but got no response. The pictures in the listing weren’t good enough to tell the difference. You might examine anything of less than well established provenance carefully.

Me? I just sent the whole lot of calipers to Eric to rebuild.

That's why I posted; I was finding the same thing as you describe. I bought the bits at McMaster-Carr. Even they note that these bits are also referred to as polydrive. The bits are listed as RIBE, though. And, the image looks like a Ribe bit.

KC Tools didn't have any socket bits in stock or I would've bought them there since they are listed as Ribe.

I stay away from Amazon since they don't police for fakes and there's too many "recommended sellers" that have bought product placement.

I can report that the MCMaster-Carr Ribe bits fit perfectly!