Thats a nice problem to have!
I rode from Europe to Australia with my girlfriend
We spent 6 months on the trip, but now I think 8-9 months would´ve been good to have, as there is so much to see and do in each country. And if I was in Thailand and had more time, I definitely would´ve included Cambodia and Laos into the list as well, been to them before and theyre both great. Too bad you cannot enter Vietnam or Burma with your own bike.
All in all it was a great trip, probably the best I´ve ever done, and something we will never forget. Everywhere the people we met were very friendly, especially in Iran, Pakistan and Indonesia. Before the trip we thought those would be the more suspicious countries on our way, but they actually turned out to be the best. I want to go to those countries again some time.
Sending the bike back home from Australia cost around 500 euros total (by ship, and not including costs at the other end, it hasnt arrived yet and is expected to take 42 days in transit)... could have sent by air, too, but then the costs would´ve almost tripled.
So if you got time to wait, freighting by sea to anywhere on the globe doesnt really cost much, thats something thats good to keep in mind, when you do the planning.
You probably can go around the world in 1 year, but I´d prefer to have more time for doing that.