Havoline was all I used before I found this site and it fouled up my view of oil. It always did me good. All of my engines are flat tappet motors, so I have been sticking with the HDDO's for a while now, but am thinking of making the switch back. The 30, 40, 10w-40, and 20w-50 still have a good ad pack if you look at their site and look in the motorcycle UOA section. When I put a new set of heads on my sbc 350 out of my work truck at 100k, it still looked like brand new inside. Had the oil pan off too, and the bottom end was also spotless. I have really been considering going back. At $1.99 a qt, it would be a good time to stock up. Thanks for sharing. Their 20w-50 is a smooth oil. You'd probably like it.