Trek makes both road bicycles in a range of frame and wheel sizes to accommodate cyclists from under 5 foot 2 inches, up to 6 foot 4 inches tall. Child sizes are also available. Because physical attributes vary from person to person, even people of the same height may need bikes that are different in frame and wheel size. Saddle size, height and position, wheel size and other factors also need consideration when determining which Trek bike to choose. Ultimately, your decision will depend on how the bike feels and rides for you.
Measure your height. Compare that measurement to the Trek bike size charts on the Trek website, where Trek recommends different frame sizes for various heights. This helps to narrow the size choices. If you are between sizes, Trek recommends choosing the next larger frame for your height.
Visit a bike shop that carries Trek bicycles to try bikes for size. Select a bike that corresponds to the size listed on the Trek website for your height.
Straddle the bike. Check the distance from your crotch to the top bar of the bicycle frame. The distance should be approximately 1 to 2 inches.
Set the bicycle saddle to the highest position possible. Sit on the bicycle saddle. Place your foot on one of the pedals in the down position. Examine the angle of your leg. If your leg is perfectly straight, lower the saddle until there is a slight bend in your leg. If your leg is bent beyond a slight angle, select a bike with a larger frame and smaller wheel size.
Test ride the bike to determine if it is a good fit. If necessary, adjust the seat height, position and angle and the handlebar height and position.