Road bikes come in various styles, designed for different types of riding and rider preferences. The frames are made from steel, aluminum or carbon fiber, and, depending on the size and age of the bike, they use one of several tire sizes: 26", 27 1/4" and 700C. Road bike frames are all measured the same way, using the the seat tube length. Here are several popular road bike styles, each with detailed measuring instructions and a frame diagram showing where to measure.
What style road bike do you have?
Classic Road Bike
A classic road bike has a top tube that is parallel to the ground.
Compact Road Bike
A compact road bike has a top tube that slopes slightly downward from the head tube to the seat tube.
Mixte Road Bike
A mixte bike has a step-thru frame with two downward sloping tubes running the full length of the bike.