How To Measure A Bicycle Frame Size
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Whether you are shopping for a new bike or selling one of your old bikes, one of the main sizing measurements used will be the bike frame size. If you’re anything like I was when I first got into cycling, you have no clue what that actually means.
If you’re selling your bike and just need to know the measurement, you should first look around on your bike. Usually, the size of the frame is listed somewhere on the bike. The size is usually under your seat stem but on some bikes, it can be in a different place. So, look around.
Obviously, you know it determines the size of the frame of your bike, but how is the frame size measured? Where do you start your measurement, where does the measurement end and why does the frame size matter when choosing your new bike.
Where Does Your Frame Size Measurement Start and Stop?
To measure your frame, you’ll need some kind of tape measure. You could use a sewing tape measure if it’s long enough or a cased tape measure. When you are measuring the size of your frame, you will want to start from the middle of the crank axle and go to the top of the seat post stem.
The frame is measured without the extra components on the bike. So, if your seat and seat post are on the bike, make sure not to measure them. You want to stop at the top of the seat stem.
Also, if you have a crank axle and pedals on the bike, make sure to start from the middle of where your pedals connect to the frame. That is your crank axle.
Once you have measured your frame, you now have your frame size. However, depending on whether you are measuring a road bike or a mountain bike, the measurements should be in a different unit of measurement.
Mountain bike frames are measured in inches, while road bike frames are measured in Centimeters. If you have a measuring tape that only has one or the other, you can use google to convert to the other measurement. If 60 centimeters was your measurement, type in google “60 cm to inches” or if 24 inches was your measurement and you need to convert to centimeters then type in “24 inches to cm”.
Why Does Frame Size Matter When Choosing a Bike?
Having the proper size frame for your body size promotes the ideal poster the bike manufacturer intended for their bike. If you have a bike frame that is too small for you, you will be scrunched up and hunched over while riding.
On the other hand, if your bike is too big, you may strain to operate the bike and it can cause injury over time. A bike that is too small can also cause injury over time due to incorrect postering.
You want to make sure that the bike you get is the right size for you. Having the right size bike for you can also make you a faster rider. First due to the comfort and ease of use when riding a properly fitted bike. The other reason is a properly sized bike will put you in the best and most aerodynamic position you can possibly be in.