How to Pick the Right Frame Size of Mountain Bike

Mountain bike frames are measured in inches.

Mountain bike frames are very forgiving. Mountain bike frames are measured in inches, and most people can fit a bike within a range of two inches, but it is best to get dialed in to the right size. With all the odd configurations of mountain bikes, you can't use the old-school, top-tube-stand-over measurement anymore. You need to use the pedal to leg extension to get your size.

Things You'll Need

• 4mm hex wrench

Instructions

1. Loosen the quick-release lever on the seat post under the seat. If the seat doesn't have one, use a 4mm hex wrench to loosen the set-screw on the bike frame that holds the seat post.

2. Get down at eye level with the seat. Pull the seat up or down to get it even with the handlebars. Tighten the seat post.

3. Get on the bike. Push the pedal all the way to the bottom of the pedal stroke.

4. Look at your knee. If your knee is bent more than five degrees, your bike is too small. Test a bike that is one inch bigger. For example, if you are sitting on a 17-inch bike, move up to an 18-inch bike.

5. Get on an 18-inch bike. Put the pedal to the bottom of the stroke. If your knee is almost straight, or you have to stretch to reach the bottom of the stroke, the bike is too big. Move down to a 17-inch frame.

Tips & Warnings

• The measurements here are for examples. Mountain bike frames run between 16 and 21 inches. Some bike manufactures even produce half-sizes. If you are approximately 5 feet 10 inches in height, the first bike you should test is a 18-inch.