Mine now has 19.5 hours, it made oil for the first 10, Yamaha told me to change it at 10 hours. It had stopped making oil by then, I changed it with the Yam Synthetic and ran the hell out of it the last 2 weeks, hasnt made oil since. Whats the best gear oil to use, is there a sythetic?Last edited by mike dominick on August 1st, 2012, 2:43 pm, edited 2 times in total.