Like others said, thats too open a question to really give accurate answers. Depends on which way you want to go, and how you like to travel. Reading about areas that you plan to go to will help a lot.
From Singapore, I think you can go overland to Malaysia, Thailand, Cambodia and Laos. But from then on it gets much more complicated, as its practically impossible to go with your own vehicle into Vietnam or Burma, though you can go to those countries without a vehicle. China could also be possible, but very very expensive, and take lots of time to arrange it. Riding through all of China still maybe not possible.
If your wanting to head from there towards Europe, you can ship the bike to India, and from there its possible to ride all the way. Pakistan may be a problem just now, and its unclear how the situation there will develop. Iran and Turkey both very nice, warm people and lots and lots to see. It is highly advisable you arrange a carnet for the bike before setting off, if you do that route.