Pedals will be replaced for clipless ...
Seat will be replaced for a skinnier one ...
Cranks will get longer ...
Air pressure (tires, eh) will become a little more critical ...
Gearing will be on the low 70's ...
Handlebars will be replaced for bullhorns ...
Freewheel will be replaced for fixed gear.
Gradual man/machine improvement
And you will be climbing hills you never dreamed off.
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