What to Look For
Wraparound sunglasses offer the best protection from all angles while cycling. Better pairs geared specifically to the sports minded offer interchangeable lenses with differing shades and degrees of darkness. This allows you to tailor your sunglasses to fit the ride conditions. Be sure to choose polarized lenses for the best anti-glare and aim for those with 100-percent UV protection.
For trail riding, amber or rose-colored sunglasses offer clarity unsurpassed by darker lenses while still offering protection from the sun when crossing clearings.
For hitting the road, wraparound styles protect you from glare and reflection from the sides as well as straight ahead.
Oakley offers several cycling sunglasses including the Flak Jacket. Kaenon's Polarized Variant offers high-contrast lenses and Zeal's Optics Maestro offers special "sticky" type ear and nose grips that get stickier the more you sweat for a non-slip ride.
Before buying a pair of sunglasses, try them on with your helmet. Fit is everything. One pair may feel fine without the helmet on but squish with the added layers against your ears. Avoid sunglasses that do not offer UV protection. Non-polarized lenses do not reduce the glare from reflected sunlight as well as polarized lenses do. Size varies between styles and brands. Always try on a pair of sunglasses before purchasing.
Where to Buy
Good pairs of cycling glasses can be found at the larger sporting goods stores, such as Sports Authority, Dick's, or Modell's. Independent bike stores offer a higher-end and better variety than chain stores do. The cycling-specific stores tend to stock only styles they know to work well with cycling. Chain stores stock general sports sunglasses, some of which may not work well under helmets on long rides.
Non-interchangeable-lens cycling sunglasses start around $75 and go up to $150. For high-quality sunglasses with changeable lenses, expect to pay $100 to $200, including a set of three to four different colored lenses.
Do some comparison shopping before you buy. You can often find good deals online after you've checked availability and prices at your local stores. For prescription cycling sunglasses, compare options at your local eye care center with those available through online sources for sports prescription sunglasses.
Most high-end sunglasses include a hard case. For interchangeable lenses, consider adding a second case to carry the other lenses with you in case of changing light conditions. If you are prone to taking your sunglasses on and off, add a neckstrap so you can let them hang within reach. Sport-specific stretch bands attach to the ear pieces and help hold them on to your head; these work if you constantly find yourself pushing your glasses back up your nose. However, glasses that fit properly tend to stay put.
When purchasing a pair of sunglasses, bring your cycling helmet. Try the glasses on with the helmet. Jump up and down several times, with your head in the approximate angle you hold it while cycling. If the sunglasses slide while you are doing this, then they are going to move around and slide while you are riding. Try a different pair.