Broken Dekerf

[CTK]

New seat tube needed...

https://www.ebay.co.uk/itm/35760411...FvPYc0ivh3XrUClpF+s=|tkp:Bk9SR8CT7amnZg&pfm=0

 

[basketcase]

What would cause a break like that, there - Seat post out too far?

 

[bikeworkshop]

What would cause a break like that, there - Seat post out too far?

Imo Some numpty clamped it in bike stand QR jaws without noticing the cable boss.
I've seen this done

 

[PanoIgano]

Imo Some numpty clamped it in bike stand QR jaws without noticing the cable boss.
I've seen this done

I would say so too as this area is pressed: