I'm so glad you asked this question. My wife invented and patented a product specifically for long hair riders. It is called the wrapter and we have been pretty succesful the past two years selling them online and at the motorcycle shows. If anyone wants one for their wife send me a PM.
It rolls up like a condom (hair protection) her website is here Clicky
I hope you don't mind but I have a daughter, nieces and lady friends who are sports minded (from snow skiing/snow boarding to softball to hiking/fishing/rock climbing) so I've put the link on my facebook page.
They're always looking for solutions and this may just fit the bill for them.