I have come across a rather unusual stem.
The square section which is straight on most stems I have seen is twisted on the one.
I have attached a picture of the square section and hope some one can explain its use.
I do not think it is a manufacturing defect, but?
Mel
mrmel.mrmel@gmail.com

Hi Mel,
That's correct, no idea of why its like that, I remember the first one I seen I wondered if the customer had forced the crown so hard it had twisted it.

you can see on the picture when it is transition from straight to twist, as usual operator error Magila gorilla fingers.

I actually straighten it but I must have gone too far the other way!
Mel

I found this page in a Swiss repairer note book.

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