Definitely Mobil 1 Not called MX4T anymore, it is called:
Mobil 1 Racing 4T
It is made specifically FOR motorcycles, and is safe on a wet clutch...
Best part is that it is available at your local AutoZone, unlike Amsoil where you either have to order off the net or find a dealer (good luck, I have 1 in my area, and he never answers).
Also think about the filter you use, Hoda is good but not cheap.
I use the Bosch 3323, and love it, it is longer than the Honda, and has more filter media.