Exposure Race Mk17 front light review

The Exposure Race Mk17 sits at the bottom of Exposure’s off-road capable light range with Reflex Technology.

It can kick out up to 1,700 lumens (bumping up to 2,600 in Reflex mode) on full power, compared to the 1,600 (2,400 Reflex) lumens of its Mk16 predecessor.

The light is mostly a winner, bringing unlit minor roads and off-road gravel trails to life. However, the non-standard charge port is a niggle, while the clamp is quite fiddly.

Exposure Race Mk17 front light specifications and details

Exposure says the Race Mk17 is best suited to cross-country racers or weight-conscious gravel riders and bikepackers.

It sports two white LEDs, with the brand’s Toro Mk14 stepping up to three, the MaXx-D Mk15 to four, while the Six Pack Mk13 has six.

All of the aforementioned lights incorporate the brand’s Reflex Technology, a feature where the light’s output is adjusted automatically based on your effort and road or trail conditions.

If the in-built accelerometers detect you’re riding fast or over bumps, the light will increase its output. Likewise, it will intuitively dim on slower sections, such as climbs.

There’s an OLED display on the rear of the unit, which displays the mode you’re in, run time remaining in hours and minutes, and battery percentage.

Using the built-in Optimised Mode Selector, you can select between 10 different modes to find the best lighting arrangement for your particular route, trail or conditions.

The first three modes offer a Reflex function in the highest setting.

For some, this might be too much choice, but I welcome being able to fine-tune settings to my specific riding.

All 10 modes and their respective battery lives are engraved on the underside of the light body.

Exposure incorporates ‘ITM’ technology – patented circuitry that self-regulates the LEDs' temperature to maximise output smartly and improve battery life.

Depending on the mode used, you’ll get anywhere between 2 and 36 hours of run time.

Also in the box is the brand’s QR Handlebar Bracket, with 31.8mm and 35mm spacers, along with a charger and quick-start guide.

I weighed the light at 196g on my Scales of Truth (10g heavier than claimed).

Exposure Race Mk17 front light performance

I tested the Race Mk17 on a variety of road and gravel rides, culminating in a 330km audax.

Illumination is excellent on unlit minor roads. I was able to see and prepare accordingly for potholes and debris in the road, although I found I wanted to quickly turn the brightness down when I met an oncoming car to avoid dazzling them.

I could even spot a black cat napping, then nonchalantly adjusting its position to avoid me with plenty of time to spare.

The audax began at 5.30am, so I had to use the light for the first couple of hours and then again after 7pm until I arrived home at 11pm.

After five hours of use, switching between a range of settings in Program 4 (of 10), I had exactly 60 per cent of battery life remaining.

I’m confident the light would last throughout the night if I needed it to, and I found the remaining time displayed on the screen (which changes to reflect the mode you’re in) was accurate.

On its highest outputs, the light felt a little like overkill for riding in twilight hours, but was confidence-inspiring in the pitch-black Forest of Dean.

On medium-technical trails, the illumination level is good if you’re using one of the brighter modes. That said, I wasn’t able to ride off-road terrain with quite the same amount of urgency as in the daytime.

The beam spread of the light is impressive, offering plenty of coverage with ample illumination thrown forwards down the road or trail.

Although I experimented with the three Reflex modes, I settled on using the fixed-lumen modes for the majority of testing.

I didn’t really notice the changes in lumen output on the road or trail, other than while braking hard, when I could see the light dimming a little.

Compared to some other Reflex-capable Exposure lights, the Race Mk17 is a little lower-powered, suggesting the differences might not be as pronounced as Alex Evans has noted, for example in his Exposure MaXx-D Mk15 review.

Moreover, the light only offers low and high modes when using the Reflex function, and when I had to turn it onto the low mode on the road to avoid dazzling car drivers, I found the brightness a little too dim.

Switching between the various modes is intuitive, by pressing the ‘Function’ button to cycle between the two or three modes available on each program.

Changing between programs is less straightforward and too complicated to perform on the move.

With the light turned off, you hold the ‘Function’ button down until it emits a series of flashes. You then repeatedly press the Function button to cycle through the programs, before stopping at the one you want.

The underside of the unit has a laser-printed table of the programs and light settings therein.

Physical installation is another area where the overall package could be simplified.

The included mount is fiddly to install, comprising four pieces: two parts to the mount body, a 4mm hex bolt and an appropriate handlebar shim.

The two pieces that make up the main mount body slot together using a jigsaw-style fitting, which can be fiddly to lock into place while simultaneously trying to hold the mount around the handlebar.

Although I tested the light in generally warm conditions, I have found with previous Exposure lights with this bracket that the red button (which is unchanged compared to those lights) is prone to freezing, which can be deeply irritating.

I’d also like to see Exposure switch to a more common Micro USB or USB-C charge port rather than the proprietary port it uses.

It would mean you don't need to carry a specific cable with you, while other devices are moving towards USB-C thanks to recent EU legislation changes.

I performed a run time test using the High mode on Program 4, which Exposure says should last for 1 hour 58 minutes.

The light lasted for 1 hour 59 minutes before the brightness dipped a little (still more than enough to get me home). It then lasted another 2 hours and 12 minutes before fully dying, which is very impressive.

It took 2 hours and 12 minutes for the light to recharge fully from empty.

Finally, there’s no getting away from the fact the Race Mk17 is a pricey light.

Magicshine’s Ray 2600B Smart Remote Bike Light retails for $149 (and should launch in the UK soon), half the price of the Race Mk17 for continuous 2,600-lumen brightness.

Jack Evans found it to be a brilliant option and could only notably fault its glitchy app and the lack of a mode indicator.

While a compelling price-driven option over the Exposure, the well-established build quality of Exposure’s lights should mean it’ll last for years.

Exposure Race Mk17 front light bottom line

Exposure’s Race Mk17 is another excellent light from the British brand, with typically robust build quality and a slew of settings to choose from to suit your lighting needs.

It performed particularly adeptly on the road and medium-technical gravel terrain, although I would opt for a more powerful front light from Exposure’s range if you’re frequently heading off-road at night.

A fiddly mount and non-standard charging cable are the standout issues.