Damage to exhaust valves?

Machine shop found 8 bent exhaust valves. No damage to pistons, timing was dead on when I pulled the head, chain isn't stretched either... any ideas?

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: BMW Head Gasket Replacement

[Wayne 962]

I'd say the only other plausible explanation is that the engine had some type of over-rev event. Such could easily come from a mis-shift while shifting. Having all eight valves bent seems to point to this scenario.

- Wayne

[bostogrun]

$$$ shift

[A930Rocket]

Do they look like this:

This was the money shift at Road Atlanta, downshifting to 3rd, but got 1st instead...