Use a soft tape or string
Take the measurement around the same spot where your helmet is meant to sit, not higher on the crown.
Helmet sizing
A better fit improves comfort and helps the helmet do its job. Measure once, match the size band, and fine-tune with the liner kit.
How to measure
The easiest way is to measure where a hat would sit. That puts the tape just above the ears and across the forehead, which is the best starting point for helmet fit.
Take the measurement around the same spot where your helmet is meant to sit, not higher on the crown.
Compare the result with the size ranges below. If you are between sizes, choose the larger helmet and fine-tune the fit with the surrounding size liner kit.
A correctly fitted helmet should feel snug and stay level without tipping back, twisting, or drifting down.
Size bands
The three shell sizes are adjusted with sizing liners. That means fit changes are straightforward once the shell family is right.
Best fit for smaller heads. If you are buying for a child or someone without a matching shell size, start here.
This range includes the S1 Lifer Helmet, Retro Lifer Helmet, Lifer Visor Helmet, and related fit options.
Choose this for larger heads. It keeps the fit straightforward and avoids forcing a smaller shell to do the wrong job.
Liner system
The Mini Lifer, Lifer, and Mega Lifer are three different shell sizes. If you land between sizes, it is usually best to move up to the larger shell and use the surrounding size liner kit to tighten the fit the right way.
Fit check
The helmet should sit level on the head, about midway down the forehead, with the straps adjusted so the shell stays put when you move.
Still unsure?
Use the size guide, then move back into the shop with confidence. If you are still in between options, reach out and we’ll help you sort the fit.
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