My girlfriend's brother rode around Europe by himself this summer, he had a great time. I know fuck all about bikes so I don't know what he rode, except that it was a Honda and it was fast. He also wiped out in Italy, but stuff like that is all part of the adventure. Good luck to you if you get around to doing it, you'll have a killer time.
PS- Has anyone seen that show Long Way Home about Ewan McGregor riding his bike from London tp New York? You should try and watch it, I found it a great watch.