The Exposure Zenith MK4 is a helmet-mounted bike light built for riders who take night riding seriously. Whether you’re tackling technical trails after dark, riding gravel into the evening, or heading out on multi-day bikepacking trips, the Zenith MK4 offers a powerful beam, intuitive controls, and rugged reliability—all in a compact, self-contained unit.
Lightweight and Durable Design
Weighing just 150g, the Zenith MK4 is ideal for helmet use. It’s CNC-machined from anodised aluminium, giving it a premium feel and excellent durability. The compact shape sits snugly on your helmet without adding bulk or throwing off your balance. It’s IP65-rated for water and dust resistance, so it’ll handle wet rides, muddy trails, and dusty gravel roads without issue.
The build quality is classic Exposure: clean lines, solid materials, and no external battery packs or wires to worry about. Everything is housed in one sleek unit, which makes setup simple and reduces the chance of failure during long rides.
Bright, Focused Beam for Technical Terrain
The Zenith MK4 delivers up to 2200 lumens—more than enough for helmet-mounted use. The beam pattern is well-tuned for trail riding: wide enough to illuminate your surroundings, but focused enough to highlight corners, roots, and obstacles as you move your head.
This directional lighting is a huge advantage on technical terrain. Unlike bar-mounted lights that only point straight ahead, the MK4 follows your line of sight, helping you spot hazards earlier and ride more confidently. The beam is clean and consistent, with no harsh hotspots or distracting shadows.
Tap-Control and Programmable Modes
Exposure’s TapTech system lets you change modes by tapping the light or your helmet—no need to fumble for buttons mid-ride. It’s responsive and works well even with gloves. You can also manually cycle through eight brightness modes to suit your ride length and terrain.
While the MK4 doesn’t include Reflex or SYNC technology found in Exposure’s larger lights, it still offers plenty of flexibility. You can customise brightness levels and runtimes to match your needs, whether you’re out for a quick evening spin or a multi-hour adventure.
Battery Life and Charging
Inside the MK4 is a 5000mAh lithium-ion battery. Depending on the mode, you’ll get anywhere from 1.5 to 36 hours of runtime. In high-output mode, expect around 2 hours of bright, consistent light. Lower modes stretch that significantly, making it suitable for longer rides or multi-day trips.
Charging is via USB-C, and the MK4 supports fast charging. You’ll get a full charge in under five hours. While it doesn’t double as a power bank like some of Exposure’s bar-mounted lights, the battery performance is reliable and predictable.
A rear LED indicator shows battery status, and there’s a laser-etched chart on the body that lists expected runtimes for each mode—a handy reference when planning longer rides.
Helmet Mounting Made Easy
The Zenith MK4 comes with Exposure’s vent mount, which clips securely into most modern helmets. It’s low-profile, stable, and includes a lanyard for extra security. The light sits close to the helmet shell, reducing wobble and keeping your setup streamlined.
If your helmet has narrow vents, you might need to adapt the mount slightly, but for most riders, it’s a plug-and-play solution. Exposure also offers optional bar mounts, but the MK4 is clearly designed for helmet use.
Real-World Performance
On the trail, the MK4 feels like an extension of your vision. It tracks with your head, lighting up corners and trail features before your bar light catches up. This makes a big difference on fast descents and tight switchbacks.
Gravel riders will appreciate the MK4’s ability to highlight road surfaces, trail junctions, and wildlife during early morning or late evening rides. Its compact size and long runtime make it ideal for mixed-surface adventures.
Bikepackers benefit from its simplicity and reliability. There are no cables, no external batteries, and no complex settings to manage. Just charge it, mount it, and ride. It’s tough enough to survive multi-day trips and intuitive enough to use in the dark.
Is It Worth the Price?
At £295 RRP, the Zenith MK4 is a premium helmet light. It’s not aimed at casual commuters—it’s built for riders who need serious performance in demanding conditions.
Compared to competitors like the Lupine Piko or Magicshine MJ-900S, the MK4 stands out for its self-contained design, tap-control switching, and refined beam pattern. It’s not overloaded with features, but everything it does, it does well.
If you ride at night regularly and want a helmet light that’s powerful, reliable, and easy to use, the Zenith MK4 is a solid investment.
Final Thoughts
The Exposure Zenith MK4 is a compact, high-performance helmet light that delivers where it matters. It’s bright enough for technical trails, smart enough to control with a tap, and tough enough to handle real-world riding conditions.
Whether you’re mountain biking, gravel riding, or bikepacking, the MK4 gives you the confidence to ride further, faster, and later into the night. It’s not the cheapest option, but for riders who value quality and reliability, it’s one of the best helmet lights available.
