Smith I/O

Find your size

• Measure the circumference of the largest part of your head
• Wrap a tape measure just above your ears and about 1 inch above your eyebrows
• Use brand sizing charts to find your size
• If you can, try helmets on in-person with your goggles

Fit tips

• A good helmet should feel snug but not tight
• If the helmet rocks back and forth or shifts from side to side, the fit is too loose
• It should sit level on your head no more than 1 inch above your eyebrows

Key features:

• Vents: Let cool air in and warm air out. Adjustable vents help fine-tune airflow
• Liners: Adjust liners or ear pads for warmth
• Goggles compatibility: Fit snugly to the top of the goggles without gaps

Happy riding!

Types of bike helmets

• Mountain bike: Rear-head coverage for off-road trails; often includes added ventilation
• Road bike: Lightweight, aerodynamic; designed for maximum airflow
• Recreational cycling: Budget-friendly choice for casual riding

Fit tips 

• Measure the largest part of your head with a flexible measuring tape (or use string, then measure it)
• Check the brand's sizing chart
• Aim for a snug fit 
• Between sizes? Choose the smaller size 

Added protection 

Look for technologies that reduce rotational forces during a crash, like Mips, WaveCel or KinetiCore.

Features 

• Vents: More vents improve airflow and reduce weight
• Visor/brim: Keeps the sun out of your eyes
• Chin bars: Extra protection for downhill mountain biking

Understand lens shapes

• Cylindrical: More affordable, but can cause more glare and slightly limit peripheral vision
• Spherical: Better peripheral vision, less distortion and less glare. Cost more than cylindrical lenses
• Toric: Offer improved optical clarity and reduced distortion—at a higher price point

Light transmission (VLT)

VLT is the percentage of light that passes through the lens to reach your eyes

• Bright conditions: Look for less than 25%
• Partly cloudy: Aim for between 25%-50%
• Overcast, stormy or low-light: Look for 50% or higher
• Night riding: Use clear goggles or 80%-100%

Other features:

• Low bridge fit: Ideal for those with higher cheekbones or lower nose bridges
• Interchangeable lenses for easy swaps
• Photochromic lenses adjust to changing light
• Extra lens included: Two lenses for different light conditions