I am a Dermatologist and a cyclist in California. I see and treat skin cancer every day in my office, especially on the face, ears and neck.
I have been seeking a way to fully protect my ears and neck and have as little facial skin exposed that would need sun screen... (SPF 70 by the way)
I see enough really horrible skin cancer that it is easy for me to wear a long sleeve jersey and long cycling tights even in the summer. I even wear full finger gloves...
I share with you a new accessory for my helmet. It is a vented sun cape that meets and exceed my design requirements. Those requirements are, full sun protection, venting and light weight fabric....the only downside is it is a little dorky looking... but if you saw the skin cancer that I see in my Dermatology office every day that would not bother you very much. I look dorky enough to begin with because I am wearing long sleeves and long tights anyway
I use the detachable sun cape from an Outdoor Reasearch SunRunner hat ( $30 at REI )
The only modification was the cutting off of the cape snap tabs and cutting 1/8 inch holes to fit between where the plastic helmet harness snaps into the body of the helmet. I removed the helmet chin strap and threaded it through the upper rear vent of the cape, It is a lot easiet to do than to verbally explain