Bent cog in cassette, how?

[cetuximab]

https://twitter.com/stegelmeier/status/814576634791677952https://twitter.com/stegelmeier/status/814576634791677952

How often do you see this?

This is my hardtail cassette. The fourth cog is bent.

How does one bend these? Am I shifting wrong?

Thanks

Sorry tried to put the picture in the post three different ways. So I put in a link.

[Cicli]

Weird, is the cog bent or a toof?
Can you post a photo?

[AngryScientist]

possible something [hard] got caught between the chain and the cog under power?

[DfCas]

I bent one in an 8speed XTR cassette once. I quit buying XTR cassettes after that and used XT's. Basic steel is best for cassettes, I think.

[Hindmost]

Which cog do you put your chain whip on?

[bikinchris]

I bent a cog before, but it was on a tandem and it was a knock off of a Campy cog made with cheaper materials.

[adrien]

It has happened to me, with debris in there (a branch, under power).

That said, this looks like it may have dug the cassette into the carrier. I'd pull the cassette and have a look if I were you.

[berserk87]

I have a friend that had this happen last year. What caused it remains a mystery.

[bart998]

You beast!