HJC RPHA 12N HEDGEHOG MC-1SF
The RPHA 12N is HJC's race-bred full-face. The PIM EVO shell layers carbon, carbon-aramid and fibreglass into a light, stiff structure shaped for a tucked riding position, and the Carbon... Read More
The RPHA 12N is HJC's race-bred full-face. The PIM EVO shell layers carbon, carbon-aramid and fibreglass into a light, stiff structure shaped for a tucked riding position, and the Carbon colorways step up to a carbon outer shell.
The HJ-42 curved race shield runs on a two-way pivot ratchet, arrives Pinlock-ready and comes tear-off prepared. The RPHA Premium Fit interior uses cheek pads that interchange across the whole size run, so the fit can be dialled in without changing helmet size, and they pull out through an emergency tab.
Features
- DOT FMVSS 218 and ECE 22.06 certified
- PIM EVO shell — carbon, carbon-aramid, fibreglass and organic fibre composite; carbon shell on Carbon colorways
- HJ-42 curved race shield with two-way pivot ratchet, tear-off prepared, 99% UV protection
- Pinlock-ready (DKS495 lens)
- ACS Advanced Channeling Ventilation — 4 intakes, 3 exhausts
- RPHA Premium Fit interior: anti-bacterial, moisture-wicking, cheek pads interchangeable across all sizes
- Emergency Kit cheek pads with pull tab
Specs
- Certification: DOT FMVSS 218 · ECE 22.06
- Shell: PIM EVO composite (carbon on Carbon colorways)
- Shield: HJ-42, Pinlock-ready, tear-off prepared
- Ventilation: ACS — 4 intakes / 3 exhausts
- Interior: RPHA Premium Fit, removable/washable
How to measure
Wrap a cloth tape measure horizontally around the fullest part of your head, about 1 inch (2.5 cm) above the eyebrows. Repeat a few times and use the largest measurement. The chart is a starting point — always try the helmet on for final fit.
HJC size chart
| Size | Head circumference (cm) | Head circumference (inches) | Hat size |
|---|---|---|---|
| 3XS | 50-51 | 19 3/4 - 20 1/8 | 6 1/4 - 6 3/8 |
| 2XS | 52-53 | 20 1/2 - 20 7/8 | 6 1/2 - 6 5/8 |
| XS | 54-55 | 21 1/4 - 21 5/8 | 6 3/4 - 6 7/8 |
| S | 55-56 | 21 5/8 - 22 | 6 7/8 - 7 |
| M | 57-58 | 22 3/8 - 22 7/8 | 7 1/8 - 7 1/4 |
| L | 58-59 | 22 7/8 - 23 1/4 | 7 1/4 - 7 3/8 |
| XL | 60-61 | 23 5/8 - 24 | 7 1/2 - 7 5/8 |
| 2XL | 62-63 | 24 3/8 - 24 3/4 | 7 3/4 - 7 7/8 |
| 3XL | 64-65 | 25 1/8 - 25 1/2 | 8 - 8 1/8 |
| 4XL | 66-67 | 26 - 26 3/8 | 8 1/4 - 8 3/8 |
| 5XL | 68-69 | 26 3/4 - 27 1/8 | 8 1/2 - 8 5/8 |
Youth sizes
| Size | Head circumference (cm) | Head circumference (inches) |
|---|---|---|
| YS | 48-49 | 18 7/8 - 19 1/4 |
| YM | 50-51 | 19 5/8 - 20 1/8 |
| YL | 52-53 | 20 1/2 - 20 7/8 |
One official HJC chart covers all models (full-face, modular, open-face, half); size availability varies per model. cm values are canonical (verified on both official US and EU HJC sites); inch values follow the mathematically consistent EU print where the US page conflicts with its own cm column (M and L rows). Note: many retailers still publish HJC's LEGACY chart (XS 53-54 … 3XL 65-66), which disagrees with the current official chart — do not mix them. Youth chart is the official Y10 chart (EU site).
Manufacturer sizing data · verified July 8, 2026