
Originally Posted by
Possegal
is it a dumb question to ask what is different in a tri bike than a road bike? apologies if that is too stupid to ask.

There are no dumb questions1
hill slug is right. Generally a tri bike wil have more elements focused on aerodynamics rather than light weight (although may have both). Triathletes are not allowed to draft and thus need to take advantage of aerodynamics moreso than road cyclists who ride in together. Tri bikes will have generally have aerobar handlebars.
"Being retired from Biking...isn't that kinda like being retired from recess?" Stephen Colbert asked of Lance Armstrong