What is the correct Fuel Oil mixture ratio for a 2002 Yamaha YZ 250?

usually most people run 30:1 or 40:1 in all racing bikes it all depends on how you ride and what kind of plug you use but i woul recomend 40:1, this is a good mixture. I have been riding and working on 4 wheelers for about 10 years now and I have a 2003 Banshee and that's what I run in it. when I was younger I had a 89 RM 80 and I ran that same mixture.