Welcome aboard. I don't think that this site has many Icelanders on board.
Your question is a legitimate one, but not easy to answer. First a few questions: How much time do you have for your trip RTW, and how much money. If unlimited of each you have numerous choices. You can take to the beaten path from Turkey via Iran, Pakistan, India, Bangladesh (skip Myanmar), Thailand, Malaysia, Singapore, Indonesia (difficult), around Australia, then Japan, North America, South America, Africa, and up to Europe and Iceland. But you can also go the other way around, say via North America, Japan, Russia, China, Pakistan, India, etc. etc. There are many travel guides available, and also several motorcycle books on the subject. Look into the "Books" section of this website. There you will find (among others) four of my books and travelling around the world on a motorcycle. My full name is Werner Bausenhart. Start planning.