If on unleaded then you want Castrol XR77. I use this in all my premix bikes. Smells great and as RichG says it is a replacement for 747 for use with unleaded. Is available in Bangkok. Contact Dirtshop in Bangkok as I think they sell it, or used to. Isn't Mega Dirt in Chiang Mai? Maybe they have it. Failing that I have a couple of cases.

Agip is also available if you need it, but they have two types. The 2T race oil and the 2T kart oil. The kart oil is not imported yet but I've tested the race oil (in drag race strokers not my bike!) and also gave a bottle to my mate to test in his karts. No problems. Contact Showpow in Bangkok, he has stock.

Synthetic oils are so good these days that I wouldn't worry about the benefits of castor oil, which is a fantastic lubricant, especially if you're only dealing with a motorcycle. The castor comes into it's own at very high rpm, which is why it's still the choice for fixed gear karts.

For injector use I always stick with Shell Advance. However, TTS is also very good. Both can be used in injector and premix forms.

At Castrol Technology Center in Bangkok I sat through several tests of various 2T oils. The two makes that stood out were Castrol and Shell. The one product that was way out in front in all high performance applications was A747. But it also came last in the low speed deposit test. Which basically means it you tickle around the town then you're far more likely to foul up using 747 than some cheapo 2T oil.

The best of the rest were Castrol TTS and Shell Advance. With Shell just sneaking it most counts.

One of the test which was fun to watch was the Kawasaki GTO125 (KH125) engine being held flat out while the fuel/oil ratios went leaner and leaner. A747 ran at something like 400:1 for a handful of seconds before locking solid