Bike Perfect Verdict
Stylish, stable and sturdy with great Zeiss optics for brighter days but face spacing, tint choice and shape won’t work for everyone
Pros
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Brilliant Zeiss optics
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Firmly stable
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No upper edge gap
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Decent ventilation
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Extended depth on Spectro
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Extended wrap on Demos
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Great lens range for summer
Cons
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Dim days Spectro lenses are aftermarket
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Obstructed peripheral on Spectro
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Gap balancing on Demos
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Potential brow contact
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Kask helmet partners Koo's new Demos and Spectro sunglasses are suited for road, gravel, and cross-country usage and use a deep and deeper lens format to provide more coverage and save some money with a simpler hinge and less adjustment. If they fit your face, you like the angular styling, the optics and stability are excellent, although light tint lenses are extra for the Spectro. But let's take a dive in to see how they compare to the best mountain biking sunglasses available today.
Spectro
The Spectro is the more stylized specs of the two designs with a stepped-up top line and dramatically deep pointed lower edge extending down your nose. The pointed shape gets vents on the lower edge and two more on the brows for enough airflow to fight fogging despite the deep coverage. The upper extension of the lens means no gap across the top if you’re down in a tuck descending. The deep frame/arm junction is intrusive if you’re glancing sideways in traffic/your riding group though.
Otherwise, the clarity of the Zeiss lenses is absolutely excellent, reducing glare without polarising so much they mess with LCD computer/GPS screens. The ‘Super Bronze’ lens we tested was a dark 12% VLT best suited to a bright day with no dark sections. The five lens range in complete glasses only tops out at 23% VLT but you can now buy a 58% pink tint lens for darker days for £40.
The 3D-shaped arms with elastomer strips over the ears give a firm hold on the head though and the adjustable nose pieces click between two positions to alter how far they sit off your face. That keeps them stable and comfortable despite a relatively high weight.
Demos
Koo's Demos are a little less dramatic in style with a diagonally sloped upper frame and relatively narrow arms. You get the same brow vents and vents at the bottom of the lens but they’re not as deep as the Spectro. That gives better peripheral vision from the projecting wraparound lens and easy ventilation from underneath, but also more draught and dirt getting between your cheeks and the lens. The two-position nose pieces adjust spacing but even with them in the ‘open’ setting the glasses naturally sit high, covering eyebrows and forehead. This means more likelihood of sweat trickle or grease smear from your brows but there’s no glare gap if you’re peering upwards in a low aero tuck. They still synced fine with every helmet we tried them with and the soft, ribbed nose pieces and Megol elastomer strips on the curved, firmly sprung arms give excellent stability.
You get the same excellent Zeiss lens quality with zero distortion right across the wrap curve and the Demos with seven different colors for different light conditions. We tested the 23% VLT ‘light brown’ which gives awesome clarity and tone in bright to intermediate conditions without being too gloomy in the shade. Most of the lenses are 23-11% VLT for much brighter conditions though with only the aptly named Rose (58% VLT) tint (available in one complete set or as a £40 extra) putting a positive spin on winter weather. Price varies slightly depending on lens choice but they’re £30-40 cheaper than the Spectro making them decent value considering the quality.
Verdict
If you want deeper coverage and a more aggressive style than the Koo Open Cube sunglasses and are fine with a fixed lens in a largely sunny day tint range, then the Spectro and Demos sunglasses deliver excellent optical clarity in a stable, comfortable format. They’re particularly good if you spend a lot of time head down, looking up in an aero tuck and price is acceptable for the quality. Each design has its own fit, vision and ventilation characteristics though so ideally try both to see which works best for you and your riding.
Tech specs: Koo Spectro
- Price: $280 / £169 / €179
- Weight: 39g
- Options: Black/bronze, black/red, black/turquoise, glass/red, white/light brown, white/blue
- VLT range: 23-11%
- Frame: Full
Tech specs: Koo Demo
- Price: $225 / £139 / €149
- Weight: 36g
- Options: Blue, black/green, black/blue, black/rose, white/red, white/silver
- VLT range: 58-11%
- Frame: Full
