Amsoil or Yamaha synthetic oil

[GregF]

I am sure I am changing more than I need to but oil is cheap insurance.
It works out to about $5 a month to go 300 hours a year. That is chump change in a world with $4 gas

[1roadking]

An extra $1 or 2 per quart is cheap money. I have a 5 year warranty on my motor and that little bit extra does not bother me at all if it guarantees no warranty issues. They can't legally make you use there oil, but it wouldn't be worth the aggravation if something happened.