I never really got the 650 tri bike thing. I don't know if once the air around the bike is moving if a 650 wheel is more aero than a 700c.
as for the gearing who knows! if I had to spec a 650 wheeled racing bike I would maybe a 44/56 to makeup for the smaller wheels.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk