Triathlon Bike Frame Size

Triathlon-specific, road and time-trial bikes are the most common options when it comes to purchasing a bike for a triathlon. Determining what type of bike you want to ride is only the first step, however. Choosing a bike that is the proper size reduces your risk of injury and makes the long rides during your triathlon more comfortable. The bike frame you choose depends partly on whether you are seeking a road bike, triathlon-specific or time-trial bike. Bike frame sizes are measured in centimeters.

Time-trial and triathlon bikes are designed to perform best in flat and straight conditions. As a general guideline, use the following size chart if you are purchasing a triathlon-specific or time-trial bike. If you are 5 feet to 5 feet 3 inches tall, seek a 49- to 50-cm bike. If you are 5-foot-3 to 5-foot-6, buy a 51- to 52-cm bike. For 5-foot-6 to 5-foot-9, look for a 53- to 54-cm bike. If you're 5-foot-9 to 6 feet tall, look first at a 55- to 56-cm bike. If you are 6 feet tall to 6-foot-3, consider a 57- to 58-cm bike. If you are 6-foot-3 to 6-foot-6, look for a 60- to 61-cm bike.

Road bikes are best for courses with hills or turns and for riding in packs. If you are buying a road bike, use the following size chart as a guideline. If you are 4-foot-10 to 5 feet tall, look for a 47- to 48-cm bike. From 5 feet tall to 5-foot-3, seek a 49- to 50-cm bike. If you are 5-foot-3 to 5-foot-6, buy a 51- to 53-cm bike. For 5-foot-6 to 5-foot-9, look for a 54- to 55-cm bike. If you're 5-foot-9 to 6 feet tall, look first at a 56- to 58-cm bike. If you are 6 feet tall to 6-foot-3, consider a 58- to 60-cm bike. If you are 6-foot-3 to 6-foot-6, look for a 61- to 63-cm bike.

Bike manufacturers size their bikes differently. Thus, a 56-cm bike in one brand may differ from a 56-cm bike in another. That makes it essential to try any bike you plan to buy. Also, get fitted for your bike, which differs from finding the proper frame size. Have a qualified technician adjust the bike so that it works for your riding style and body biomechanics and so that it is adjusted to take your injury history and other factors, such as flexibility, into account, advises Tom Holland, author of "The 12-Week Triathlete." Being properly fitted will help you prevent overuse injuries and improve your cycling efficiency.

Take feel into account when you buy a bike and choose a frame size. Feel incorporates fit, comfort and the sometimes intangible element preference. Always test drive the bike model you plan to purchase to make sure the bike feels right to you. If the bike does not feel right, don't buy it, advises Ironman triathlete Ray Fauteux. Seek a bike that suits your ability and style, and tune out the chatter about which bike is lighter, higher tech or better. When you find a bike that suits you, similar to when you find a pair of running shoes that feel right, hang on to it, even if that involves saving it mainly for races and training on another bike, Fauteux advises.