The Bike List

Fox The Duncan Sport Sunglasses with Polarized Lens £165

Tested by Oliver Laverack, tester for The Bike List

Whether zooming along a country road or hammering down a fast section of singletrack there’s one thing we all dread. It’s a moment that can bring anyone to a complete halt and have you in tears quicker than a finely chopped onion. Yes, you guessed it - a fly in the eye.

Having cried too many times in front of my mates thanks to a UFI (unidentified flying insect) I generally ride with either a set of clear-lensed cycling glasses or a pair of sporty sunglasses if the sun is bright. Not only do I save myself from tears but I also get to protect my eyes the elements and nature’s missiles.

If you’re in the market for a new pair of quality cycling glasses this summer then you’ll no doubt look at all the usual brands such as Okaley, Rudy Project, Endura, Giro etc. A brand that you may not have considered is Fox who despite making mostly casual sunglasses also offer a sportier number aptly named The Duncan Sport. Designed by Fox but made by Oakley, the design is more casual with an understated sporty edge that makes them perfect for cycling and running but also means you won’t look like you’ve just finished the Tour de France when you’re enjoying a few jars in the beer garden of your local pub.

Although the design seems different from a typical Oakley offering, the build quality is just as good as you’d expect from the masters of cool eyewear. The O-Matter frame is light yet strong and integrated rubber grippers (Unobtainium ear socks) on each arm stop the frame from sliding around regardless of how much your head is bobbing around. The soft rubber (also Unobtainium) nose pad is both grippy and super comfortable and another thinner one is supplied should you have a massive honker. Weighing in at 30g it’s easy to forget you’re wearing these glasses even after a full day of them sitting on your face.

The interchangeable lens means you can fine tune the Duncan Sport sunnies to suit the conditions. Changing lens isn’t difficult and is easiest when you start by unclipping the mid section from the nose piece as the sides then slide out more easily. The polarized lens that comes with the matte black pair tested here is great for sunny and even slightly cloudy days. To make these useable in winter though you’d also need to invest in a clear or Persimmon lens better suited to flat or low light. Other lenses available are Bronze, Black Iridium, Grey, Clear, Black, Ice, Iridium and Photochromic.

Having worn the Duncan Sport sunglasses most recently for the entire 8hour Hell Rider Adventure Duathlon I was able to test them on a perfect day of extremes. The majority of both the mountain bike and run courses were directly under the sun but a few sections on both courses were through shaded woods. Impressively the polarized lens, which also makes these sunglasses good for driving on sunny days, also lets through plenty of light and offers good levels of contrast even when you’re surrounded by trees and shade. Being a scorcher of day there was no shortage of sweat which does tend to drip down the lens of the Duncan Sport but having no lower rim it tends not to hang around for long. I have had to stop and clean the lenses a few times mid-ride - best done using water or the glasses bag / cloth supplied as it doesn’t take much to scratch the lenses.

Despite this, the glasses are highly impact resistant, and pass the ANSI impact test. Fox say they are resistant against heavy objects at slow speeds and lighter objects at high speeds, so unless that insect, clod of earth or flicked-up stone is really heavy, you’re going to be safe behind these.

The only fly in the ointment is that immediately after stopping really intense exercise these glasses can fog up, so taking them off whilst you get your breath back seems to be the best way to prevent this. One thing that has really impressed me though is the excellent field of vision due to the massive lens and lack of underside frame. This design feature was vital on the Hell Rider where there was no shortage of rogue branches at eye level poking at you from the sides of the forest trails.

As well as the matte black pair tested here, the Duncan Sport sunglasses are available in Polished Black (£165/£130), Carbon Fibre (£130), Hot pink (£120), Matte Rootbeer (£120) and Silver/Grey (£120) so there are plenty of colours/lens combinations to choose from. The hardcase that’s included has room for an additional lens and is a fitting safehouse for these sunnies when not in use. In terms of value The Duncan Sport sunglasses are in line with what you’d expect to pay for an equivalent pair of premium sunglasses from Okaley or Rudy with the added bonus that you won’t see many others wearing them. The rugged case that’s included adds an extra value point but unfortunately the glasses only come with one lens as standard so anyone planning to use these all year round will need to shell out for a second lens. With clear lenses costing £45 and other tinted lenses costing an eye watering £65 or £90 that extra value point gets taken straight back. At the time of writing this review there also seems to be a distinct lack of clear lenses available in the UK so double check this before you buy.

Fox says:

Designed by Fox, developed and built by Oakley; The Duncan Sport utilizes performance technologies that meet the demands of world class athletes and innovations that have made Oakley the world leader in Performance Eyewear.

  • Durability and all day comfort of lightweight and stress resistant O Matter ® frame material.
  • Optimized peripheral view and side coverage of POLARIC ELLIPSOID™ lens geometry
  • Comes standard with HYDROPHOBIC™/Oleophobic anti-smudge lens coating
  • Comfort and performance of Three-Point Fit that holds lenses in precise optical alignment
  • Unobtanium® ear socks ensure a secure fit and become tacky when
  • TPR Fox Head Icon Accents
  • Optical precision and performance that meets all ANSI Z87.1 standards
  • Impact resistance that meets all ANSI Z87.1 standards for high-mass and high-velocity impact
  • UV protection of PLUTONITE® lens that filters out 100% of UVA / UVB / UVC & harmful blue light up to 400nm
  • Glare reduction and tuned light transmission of IRIDIUM® lens coating
  • Interchangeable lenses to optimize performance in any environment
  • Interchangeable UNOBTAINIUM® nose pad options for customizable and comfortable secure fit
  • Protective sports-specific Hard Case included with capacity for an extra lens

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At a glance

Verdict Light, comfortable, stylish and impact resistant sunglasses with interchangeable lenses and a wide field of vision ideal on and off the bike.