In a previous post, How to Measure a Bike Frame – Terminology, we discussed the basics of how to measure a bike frame and the bike terminology used when describing bike frames. Now, let’s specifically walk through the steps and explain how to measure a road bike frame. If you are unsure of any bike terminology used or need to refresh your memory, you may want to review the post listed above. Okay, but first, let me ask,
How to Measure Road Bike Frame – Do I need to know this?
Why do I need to know this? Is this useful?
Understanding how a road bike frame is measured can be useful when replacing your old bike to ensure you get a similar size frame.
I personally could have benefited from this information when I bought a used road bike once that was listed as a 56cm. If I understood how to measure the bike frame size then I would have realized that it actually was a 60cm before I bought it, not after 🙁
If you test rode a friend’s bike and they don’t know the size, you could use this to find out.
There are a variety of reasons this information could be useful. When we understand that the central piece of the bike, the part that everything else attaches to or works together with is the frame, then you realize the when you ask what size bike should i ride, you are really asking what size bike frame do i need. Getting the right sized frame is the key to a well fitting, comfortable bike, as well as a future of happy bike riding.
How to Measure Road Bike Frame – Information:
Road bike frame sizing is traditionally measured in centimeters (cm).
One inch is equal to 2.54 cm.
Depending on manufacturer, road bike frame size may be measured from the center of the bottom bracket to the center of the top tube at the point the top tube intersects the seat tube. This is known as center to center (C-C), or road bike frame size may be measured from the center of the bottom bracket to the top of the seat tube. This is known as center to top (C-T). Since Measuring a Road Bike Frame can be done either C-C or C-T, just complete both measurements at once so you have them for reference.
How to Measure Road Bike Frame – What you will need:
You will need:
Measuring Tape (If the measuring tape is standard (not metric), you will also need a calculator to convert to metric.)
How to Measure Road Bike Frame:
- If cranks are installed: measure from the center of the bolt (or dustcover covering the bolt) that secures the crankarms to the bottom bracket.
- (In the example, this would measure about 19.75 inches)
- (In the example, this would measure about 21.6 inches)
- (Above C-C example: 19.75 x 2.54 = 50.17 cm. Round to 50cm)
- (Above C-T example: 21.6 x 2.54 = 54.86 cm. Round to 55cm)
Well, that’s how to measure a bike frame, specifically a road bike frame. Questions or comments? Feel free to leave them below. – Skippy