When you’re getting ready to tackle challenging mountain trails, it’s important to have a bike that fits your frame. Rocky Mountain Bicycles has created this mountain bike size chart for men and women to help riders choose the correct steed. It shows the general height range for eight common bike sizes, ranging from the Reaper 24 youth mountain bike to their XXL Growler trail bikes. By using a proper-fit bike, you’ll have better handling and feel, which translates to more riding confidence.

Although the height ranges below are a good starting point, there are other factors to consider. Here are the three key mountain bike sizing measurements:

• Effective Top Tube Length — The horizontal distance between the head tube and seat tube. This indicates how long the bike feels when seated.
• Reach — The horizontal measurement from the bottom bracket center to the head tube center. It indicates how long the bike feels when you’re out of the saddle.
• Standover Height — Straddle your bike with your feet flat on the floor. There should be at least 2 inches of clearance between your groin and the top tube. Some aggressive riders prefer 3-5 inches.

L9 Sports and Rocky Mountain Bikes both recommend a professional fitting and test ride when purchasing a new bicycle. We offer bike fitting services at all our ski and bike shops along with new handlebars, seat posts, and other accessories to fine-tune the fit.

If you’re one of the “tweener” sizes on this bicycle size chart for men — for example, 5’8” person that can fit both a medium and a large bike — you’ll have to decide whether to size up or size down. Sizing up will give riders more stability at high speeds, which is good for open trail riding. Going a size down improves nimbleness for getting around obstacles and tight corners. The choice largely depends on your riding style and personal preference.