^ Yeah I think the seat can go higher still too, but what I meant was the crank arms are short enough not to cause any pedal strike to the ground, so it could've been much lower. Lower is better for BBs.
I can't quite make out what keeps the main frame from splaying apart, from the rider's weight. Next to the black rear brake cable, there seems to be a flexible silver stay (or chain?) running across.
The design does appear to have a lot of misgivings...
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