Biltwell Bonanza Helmet
Features Rugged, plated steel D-ring neck strap with adjustment strap end retainer Expanded polystyrene inner shell Injection-molded ABS outer shell with hand-painted finish Hand-sewn, removable, brushed Lycra® liner with contrasting... Read More
Features
- Rugged, plated steel D-ring neck strap with adjustment strap end retainer
- Expanded polystyrene inner shell
- Injection-molded ABS outer shell with hand-painted finish
- Hand-sewn, removable, brushed Lycra® liner with contrasting diamond-stitched, quilted, open-cell foam padding
How to measure
Measure the circumference of your head with a tape around the widest part, passing above the ears and eyebrows, and match it to the chart — head measurement beats hat size. Don't confuse the cm number on the tag inside a Biltwell helmet with your head measurement (that's the interior size). Fit check: grasping the chin bar and rocking the helmet should move the skin of your face without the helmet rotating; forehead/temple pressure means size up, free rotation means size down. ECE-certified Biltwells fit more snugly than comparable DOT models; accessory cheek pads in multiple thicknesses fine-tune the fit.
Current models (2026 fitment chart — Bonanza, Gringo family, Lane Splitter, Tahoe)
| Size | Head circumference (cm) | Head circumference (inches) |
|---|---|---|
| XS | 53-54 | 20.75-21.25 |
| S | 55-56 | 21.5-22.0 |
| M | 57-58 | 22.4-22.85 |
| L | 59-60 | 23.25-23.6 |
| XL | 61-62 | 23.75-24.25 |
| 2XL | 63-64 | 24.375-25.0 |
Legacy ECE R22.05-era models (2022 chart — older Gringo S ECE / closeout stock)
| Size | Head circumference (cm) | Head circumference (inches) |
|---|---|---|
| XS | 53-54.25 | 20 7/8 - 21 3/8 |
| S | 54.5-55.75 | 21 1/2 - 22 |
| M | 56-57.25 | 22 1/8 - 22 5/8 |
| L | 57.5-58.75 | 22 3/4 - 23 1/4 |
| XL | 59-60.25 | 23 3/8 - 23 7/8 |
| 2XL | 60.5-61.75 | 24 - 24 1/2 |
Biltwell publishes charts as images on product pages (no standalone sizing page). All current-production models share one unified adult chart, XS–2XL (Biltwell prints XXL → normalized 2XL; no 3XL). Older ECE R22.05-era stock ships against a DIFFERENT 2022 chart (e.g. M = 56–57.25 cm vs 57–58 current) — both included, match by model generation. No youth chart published. 'Exfil' is Biltwell's luggage line, not a helmet. Verified from biltwellinc.com product pages + chart image files 2026-07-13.
Manufacturer sizing data · verified July 13, 2026