You're going to LOVE the fit. Try it on and experience our perfect fit. If you don't love it, send it back in new and unused condition within 30 days for an exchange or full refund*. Risk free.
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Gloss Finish
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We have a very easy 30-day Return Policy! Visit our Return and Exchanges page for more information.
We stand behind our products – with a 3 year warranty against materials and workmanship for all helmets.
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Highlights
Distinct Venturi venting, a wide field of view and a fully integrated Bluetooth® Cardo communications system in the 509 Mach V Carbon Commander Helmet help turn riders into street fighters. Sleek, lightweight, powerful, and built for speed, this DOT and ECE 22.06 certified helmet features air pump ear pads, a group chat-ready DMC mesh network, and rich, noise-canceling JBL speakers.
Key Features
- Lightweight, durable hand-laid carbon fiber construction
- Fully-integrated Cardo communication system featuring in-helmet audio and microphone seamlessly allows for connecting to up to 15 riders in a group to speak and listen with auto ducking for music (mesh capability)
- Right side - Prime Control - on/off, pairing, and app-configurable button
- Left Side - Active Control - 12-volt input, volume, forward/backward controls
- Connect via Bluetooth® to your music, phone, maps, or machine
- Battery life is variable, 6-8 hours in optimal conditions
- Premium sound - JBL speakers and uniquely designed PSI (Pressurized Sound Isolation) system for passive noise cancellation and adjustable ear muffs for a custom fit and feel
- Integrated microphone + 900 mA lithium ion battery for immediate helmet startup, pairing, and communication.
- Innovative Venturi Venting System pulls moist air out without cold wind coming in Venturi Vents (Manual shutter built into interior of helmet at chin bar to allow comfortable ride) → Learn More
- Controllable Active Chase Light
- Fidlock® chinstrap for easy on and off
- Injected molded construction for lightweight and durable performance
- DOT/ECE 22.06 dual certified helmet shell
- Premium Liner for a comfortable and quiet fit
- Re-chargeable on-board battery and included charging cord
- Custom liner kits available for a custom-tuned fit → Shop Now
- Breath Deflector included
- App-driven customization, software, and feature updates for Apple and Android
- WARNING for California residents
Specs
- Starting Weight: 1670 grams
- Head Shape: Intermediate Oval
Size Guide
Not sure about your size? Try on at your local dealer!
*Street Helmets are a tighter fit due to cheekpad compression, however, they do pack out over time/use.
How to Measure
When measuring your head, use a cloth tape. Start it just above your eyebrows and circle it around the thickest point in the rear of your head and then reference the size guide above.
Scroll to the right to see more sizes
| Size | US Hat Size | Inches | Centimeters |
| X-Small | 6 5/8 - 6 3/4 | 20 7/8 - 21 1/8 | 53 - 54 |
| Small | 6 7/8 - 7 | 21 5/8 - 21 7/8 | 55 - 56 |
| Medium | 7 1/8 - 7 1/4 | 22 1/2 - 22 5/8 | 57 - 58 |
| Large | 7 3/8 - 7 1/2 | 23 1/4 - 23 1/2 | 59 - 60 |
| X-Large | 7 5/8 - 7 3/4 | 24 - 24 1/4 | 61 - 62 |
| 2X-Large | 8 | 24 3/4 - 25 | 63 - 64 |
| 3X-Large | 8 3/4 | 25 1/4 - 25 3/4 | 64 - 65 |
| 4X-Large | 9 | 26 - 26 1/4 | 66 - 67 |
| Youth Small | 6 | 18 1/8 - 18 7/8 | 47 - 48 |
| Youth Medium | 6 1/8 - 6 1/4 | 19 1/4 - 19 5/8 | 49 - 50 |
| Youth Large | 6 3/8 - 6 1/2 | 20 - 20 1/2 | 51 - 52 |
Pressure Points
When trying on a helmet, take note of any pressure points on your forehead—a sign that the helmet is too round. Pressure points on the sides of your head indicate a helmet is too oval for the shape of your head. After you buy a new helmet, try wearing it for 30 to 45 minutes to check for pressure points before using it on a ride.
Pressure Points
When trying on a helmet, take note of any pressure points on your forehead—a sign that the helmet is too round. Pressure points on the sides of your head indicate a helmet is too oval for the shape of your head. After you buy a new helmet, try wearing it for 30 to 45 minutes to check for pressure points before using it on a ride.