Frame Size Guidance

What Is Frame Size?

Frame size refers to the overall size and geometry of a bicycle frame, not just how tall it looks. In road bikes, frame size is usually expressed in centimeters (cm) and traditionally relates to the length of the seat tube.

But here’s the important part:

Frame size is not just about your height.

Two riders of the same height may need different frame sizes, depending on their body proportions and riding style.

What Is Inseam?

Your inseam is the distance from the ground to your crotch, measured along the inside of your leg.

Why inseam matters:

• It determines how high the saddle needs to be
• It affects standover clearance
• It plays a major role in selecting the correct frame size

This is why inseam is often more important than height when it comes to frame sizing.

How Inseam Affects Riding Experience

A correct inseam-based frame size helps you:

• Pedal efficiently
• Maintain proper knee alignment
• Avoid saddle discomfort
• Ride longer without fatigue

An incorrect inseam match can lead to:

• Knee pain
• Hip rocking
• Poor power transfer
• Feeling “stretched” or “cramped” on the bike

Why Frame Size Alone Is Not Enough

Frame size is only one part of bike fit.

Other critical factors include:

• Upper body length (torso & arms)
• Riding experience (beginner vs experienced)
• Flexibility
• Preferred riding posture (relaxed vs aggressive)
• Frame geometry (reach, stack, wheelbase)

That’s why a size chart copied from another brand or model can be misleading.

A size chart works only for the exact frame it was designed for.

Why “Bigger Frame Is Better” Is a Myth

Many riders assume:

“I’m between sizes, so I’ll go bigger.”

In reality, this is usually a bad choice.

A bigger frame often causes:

• Excessive reach to the handlebar
• Shoulder, neck, and lower-back pain
• Reduced control, especially for beginners
• Difficulty riding comfortably for long distances

Why Slightly Smaller Frames Are Often Better

A slightly smaller frame:

• Is easier to control
• Allows a more relaxed riding position
• Can be safely adjusted using stem and saddle setup
• Reduces strain on shoulders and lower back

In bike fitting, it’s almost always easier to make a small frame fit bigger than to make a big frame fit smaller.