Kim Young - 2013 US Skimo Champs photo: Mark GockeWhen I first started skimo racing several years ago, eye wear was a dilemna. Should I bring goggles? Do I need sun glasses? Should I go with nothing and keep it simple? Over several races I tried all those ideas. I also combed European race photos to see what the pros were doing.
Most races in the U.S. start early in the morning so eye protection from the sun isn't a big issue. Even on a clear day I figure I can squint for a couple of hours. The winter sun isn't so intense when it's low in the ski in February. Besides, I have a problem with sun glasses fogging up. Leave them behind and the issue goes away.
But when you start ripping downhill, eyes water and protection suddenly seems like a good idea. The first few races I did I left the eye protection behind and was mostly happy. I dealt with the watering eyes on the descents and didn't have to fuss with anything on the ups.
Then the Grand Targhee race happened one year and it dumped before and during the event. Suddenly, I was blinded sans eye protection right after the first climb. Anyone who's skied in a snow storm with no eye wear knows how horrible it is. I vowed right then to never race without goggles even when it's sunny. I got spoiled on the descents not fighting watering eyes trying to see where I was going.
Now, backcountry skiing with goggles on your head always leads to fogged up lenses at the top of a climb. But in skimo racing we're wearing helmets so that's usually not an issue. A helmet is the perfect way to transport eye protection in a race. I'm a huge fan of the CAMP Speed helmet. At 210 grams, it's freaking light. 
One caveat here - and I learned this the hard way - is to tape over any front vents in the helmet. If you don't you still may end up with fogged up lenses as your head sweat dispels through the vents into the goggle when they're perched on the front of the helmet during climbing.
Securing the goggles to the helmet is usually necessary to keep the strap in place during donning and removal. Nothing more frustrating than having the strap snap off the back of the helmet onto your neck. To secure the strap, simply use tape or, better yet, zip ties to hold it there. I like to customize the goggles strap even further by removing the buckle and sewing the strap to the proper length. This gives me a dedicated pair of goggles for racing. Be sure to find the lightest eyewear you can get away with.
Once you start racing with goggles at the ready you'll never want to be without them. And although I rarely ski with them in the backcountry, the option remains when paired with a light race helmet. I never have to go digging around in my pack for them. Fast transitions remain.