C91 Modular Helmet Solid

HJC C91 Modular Helmet: Everyday Comfort with Flip-Up Convenience

The HJC C91 Solid is a practical choice for commuters, cruiser riders and weekend touring. Its flip-up chin bar makes stops more convenient, while a built-in sun visor, ventilated interior and broad X-Small through 5X-Large size range help you find an everyday helmet that works for your ride and your budget.

Shell, Protection and Modular Operation

• Advanced polycarbonate composite shell: HJC uses CAD-developed shaping to balance weight, fit and comfort.
• DOT certified: This listing is for the U.S. motorcycle version of the C91.
• Glove-friendly chin-bar release: A single lever lets you raise the front at a stop. Close and securely latch the chin bar before riding.

Face Shield and Internal Sun Visor

The Pinlock-ready HJ-17 face shield uses HJC's RapidFire system for quick, tool-free shield changes. A compatible DKS088 Pinlock insert is available separately to help manage fogging. The independently operated dark internal sun visor slides into position when you need shade and retracts when conditions change.

Ventilation and Interior Comfort

The ACS ventilation system channels air through the helmet to carry heat and humidity out. SuperCool moisture-wicking, antibacterial fabric helps the interior stay comfortable. Both the crown liner and cheek pads can be removed for washing. Glasses grooves accommodate eyewear, and recessed speaker pockets provide space for a compatible communication system.

Communication Compatibility

The C91 is prepared for SMART HJC 10B and 20B Bluetooth systems, sold separately. Choose a C91-compatible system and installation kit; Bluetooth readiness does not mean a communicator is included.

Colors and Finishes

Matte Black corresponds to HJC Semi-Flat Black, Matte Pearl to Semi-Flat Pearl White, and Titanium to Semi-Flat Titanium. White and Gloss Black have gloss finishes; Nardo Grey offers a neutral gray alternative. Select a color to see its matching helmet image.

C91 Size Chart

Use the C91-specific measurements below as a starting point. Inch measurements are approximate conversions from HJC's centimeter ranges.

Size	Head Circumference (cm)	Head Circumference (inches)
X-Small	53-54 cm	20.87-21.26 in
Small	55-56 cm	21.65-22.05 in
Medium	57-58 cm	22.44-22.83 in
Large	59-60 cm	23.23-23.62 in
X-Large	61-62 cm	24.02-24.41 in
2X-Large	63-64 cm	24.80-25.20 in
3X-Large	65-66 cm	25.59-25.98 in
4X-Large	67-68 cm	26.38-26.77 in
5X-Large	69-70 cm	27.17-27.56 in

How to Measure and Check Your Fit

Wrap a soft tape horizontally around the widest part of your head, approximately one inch above your eyebrows. Try the helmet on with the strap fastened: it should feel snug and evenly supported without painful pressure points or excessive movement. A measurement alone cannot confirm fit. Visit Eagle Leather in Lakewood for help checking your size.

Manufacturer Warranty

HJC covers manufacturing defects for up to 3 years from purchase or 5 years from manufacture, whichever comes first. Coverage excludes misuse, modifications and accident damage. Keep your dated receipt and contact Eagle Leather for assistance with a warranty claim.