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Non-concave seat tube cutout points to it being a pucker track frame
Bollocks.
UCI says the commissaire has to be able to slide a credit card between the tyre and the tube. Making the cut out concave would allow one to run as tight as the UCI allows for minimal translational drag while maintaining the thick shear layer between tyre and tube which is desirable to reduce drag from the wheel rotation. On the other hand, the semicircular leading edge on that tube means that that flow is fucked before it reaches the cut out and it's never coming back, so the short flat-backed cut out is probably not doing anything apart from making the seat tube a bit less stiff than a round tube made from the same amount of material would be.
Also, it's pukka, one of many English words derived from Indian languages, in this case Hindi.
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gbj_tester
M_V
Non-concave seat tube cutout points to it being a pucker track frame as there's some UCI rule about not using the seat tube as a fairing for the rear wheel or something.
Paging @mdcc_tester ?