My 1987 $75 Craigslist Miyata mountain bike on slicks smokes fools on Litespeeds with slippery lycra and tunnel tested $200 helmets.

Why ?

The fastest part of the bike is the motor - YOU. I would say the aerodynamics of the rider are much more important than that of the cycle. 20 pounds of less ass weight trumps 456 grams of wheel weight every day of the week and twice on Sundays.