10w30 synthetic would be my recommendation.
SAE 10w30 oil or Yamaha 4 Stroke Engine Oil
Yamaha's Yamalube, 2 stroke oil is a good choice.
sw 30
Yamaha's Yamalube, 2 stroke oil should work pretty good
Yamalube motor oil
Yamalube motor oil.
a good quality 2 stroke oil
Yamalube motor oil
2-Cycle Engine oil.
I use 10W30 in my 1989 Yamaha Warrior.
yamalube 4
SAE 10W30 or yamalube 10w30