Guess I need to do a little 'splainin'. HD Syn 3 is considered legally and by most scientists to be a full synthetic. It is not a "blend", any more than Mobil 1 or the Valvoline are blends, even though both of them contain probably between 10-15 percent dino oil as the carrier for the additive package. An oil considered a blend will have both synthetic and dino oil mixed as the base. The synthetic part might be as low as 5% of the base, and it will still be called a synthetic blend.

When one of the major oil companies started making a synthetic from the "super refined" dino oil (a Group 3 oil), they were taken to court by another manufacturer of a Group 4 synthetic oil. Scientists and college types testified, and the court ruled, that the Group 3 oil was a synthetic because it was processed until all the molecules comprising the oil were of the same length long chain type. So by legal standards, and the majority of scientific opinion, oils such as HD Syn 3, Castrol Syntec, and numerous others, are full synthetics.

Are these Group 3 oils as good as the Group 4 and Group 5 synthetics? For those of us who change our oils every 2000 - 3000 miles the base stock is probably not as important as the additive package. How can you know what the additive package is? Good luck! About the only way is to have the oils analyzed and that typically costs about $75 or more. And then you need to know what additives are used for what. And just when you have it all figured out, the manufacturer changes the formulation, and doesn't tell anyone.

So here's what I think: If you find an oil, dino or synthetic, that suits you for what you consider a reasonable price, use it. If you live in a hot climate, and especially if you have a Twinkie motor, synthetic of nearly any kind will be a better choice than a dino oil. Change your oil and filter every 2k -3k miles. Ride the crap outta the bike, and smile 'til the bugs fill all the gaps between your teeth!