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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Easy Returns
We have a very easy 30-day Return Policy! Please submit a Customer Support Ticket to get a return Authorization so we can process your return or exchange.
Warranty
We stand behind our products - the 509 industry leading warranty covers every product we make in a variety of ways.
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With a maximized field of view and high-flow Venturi duct venting, the 509 Mach V Helmet sets the stage for the next evolution in moto helmets. Whether you’re splitting lanes on the freeway or zoned in on the zen of riding, this sleek, stylish DOT and ECE 22.06 certified helmet with an easy gloves-on access Fidlock® chinstrap has been built for adrenaline junkies and city weavers alike.
Key Features
- Maximized field of view
- Distinct Venturi vent ducting
- DOT and ECE 22.06 certified - global standard (EU and CA)
- Fidlock® chinstrap
- California Prop 65
Specs
- Starting Weight: 1750 grams
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Sleek and powerful shell design built specifically for speed
-
Distinct, patent pending Venturi Venting System
-
Optically superior wide field of view and plush 3D liner system for optimal fit
-
DOT and ECE 22.06 certified - US and EU standard
-
Easy, gloves on access with Fidlock magnetic chinstrap
-
Starting weight 1750g

-
Sleek and powerful shell design built specifically for speed
-
Distinct, patent pending Venturi Venting System
-
Optically superior wide field of view and plush 3D liner system for optimal fit
-
DOT and ECE 22.06 certified - US and EU standard
-
Easy, gloves on access with Fidlock magnetic chinstrap
-
Starting weight 1750g

With a maximized field of view and high-flow Venturi duct venting, the 509 Mach V Helmet sets the stage for the next evolution in moto helmets. Whether you’re splitting lanes on the freeway or zoned in on the zen of riding, this sleek, stylish DOT and ECE 22.06 certified helmet with an easy gloves-on access Fidlock® chinstrap has been built for adrenaline junkies and city weavers alike.

More than a lifestyle
When you’re riding, you’re part of something much bigger—you’re part of a community driven by a mutual understanding and shared passion for adventure.
We've got you covered.
Explore our street gear.
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.
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 |