Although road bikes are commonly used in road cycling competition, the more specialized triathlon or time trial bike may give you the edge in shorter races. These bikes have more aggressive geometry to keep your riding position aerodynamic, with shorter top tubes and wheelbases to minimize your profile to help you squeeze precious seconds off your time. Road bikes are designed to be more comfortable on much longer distances and are usually lighter to help with long climbs.
Designed to master both smooth and rough pavement, a road bike is comfortable over the most extreme distances and is designed with being lightweight as a priority. Road bikes are outfitted with drop bars, which allow the rider to make use of multiple hand positions to suit sprinting, climbing and everything in between. The most relaxed handlebar positions make them more comfortable than tri bikes over long distances. Road bike frames for competition are usually made from carbon fiber to reduce weight.
By Triathletes, For Triathletes
A triathlon bike is designed for the short distances commonly associated with the cycling portion of a triathlon or the all-out sprint of a time trial. Because endurance isn't an issue, riders tend to take a more aggressive riding position on a triathlon bike by using an aerobar setup. Bullhorn-style handlebars coupled with aerobars allow a racer to rest on their elbows, lowering their head and body into a tight aerodynamic tuck. Time trial bikes are also made from carbon fiber, but these frames are shaped to maximize wind resistance, using more material to tuck around the rear wheel and form a "wing" shape throughout the bicycle's profile.