I agree with carguydave, I'm using 20wx50w Valvoline full synthetic in my 2001 350 4x4 Yamaha Wolverine. I had no oil leaks the first 3 months I owned the ATV, (acquired the unit in 2016), before I changed to full synthetic, now my cylinder head on the left side has a film of oil from top to bottom. ATV runs great sounds great, and I'm still glad I have full synthetic in my machine. But depending on how old your machine is, it may develop some unsightly leaks.
1986 Kawasaki Bayou 300 Synthetic Engine Oil
in Kawasaki ATV Forum
Posted
I agree with carguydave, I'm using 20wx50w Valvoline full synthetic in my 2001 350 4x4 Yamaha Wolverine. I had no oil leaks the first 3 months I owned the ATV, (acquired the unit in 2016), before I changed to full synthetic, now my cylinder head on the left side has a film of oil from top to bottom. ATV runs great sounds great, and I'm still glad I have full synthetic in my machine. But depending on how old your machine is, it may develop some unsightly leaks.