Here's an article that includes some scientific data about motorcycle oil and automotive oil. The article's a little old, but still very relevant. After reading this, I now officially refuse to spend $4 a quart on non-synthetic motorcycle-specific oil when I can get Mobil-1 for the same price and with much less hassle by going to my local auto parts store. Some people might insist that you can't make up your mind on the basis of one article, and maybe that's true. Until I find an equally thorough analysis that disputes the results of this article, I'm staying with normal automotive oil.

http://www.nightrider.com/biketech/oiltest1.htm

I used automotive oil in my Warrior, and now the clutch slips. Should have used motorcycle oil! (I learn the hard way) The oil article is thinly veiled promo for Amsoil, with links on each page.

Are you sure you read the article I posted the link to? I saw no Amsoil ads or links anywhere on that page, not to mention the fact that their name was not even mentioned or tested in the article.

It's a well known fact that friction modifiers used in automotive oils cause problems for motorcycle wet clutches.

Mobil apparently makes a motorcycle version of Mobil 1.

Similarly full synthetic appear to have shear problems with the highly loaded valve gear in motorcycle engines, Pam at Powroll has posted at length on this subject.

Buy the product made for the job.........

Kiwi

The Mobil 1 15W-50 does not have friction modifiers. As for standing up to the shear forces present in motorcycle engines, that's the primary focus of the article and its tests. The results look pretty conclusive to me.

Oh, 95Warrior, the friction modifiers present in many automotive oils will definitely cause premature clutch failure in a wet clutch machine. Make sure the oil does not say "Energy conserving" in the circle that describes its rating.

so what about clutch slippage due to anti friction additives. that is the question not answered in the article.

On the pages I looked at there was a link labelled "Oilhelp". Hit that and the Amsoil stuff comes up. Nothing against Amsoil, they got great stuff.

I've been using regular 10/30 automotive oil in my quad since the day of my first oil change (second time out riding) and have not had ANY problems. I spend a buck nineteen per quart.

Did U guys know they make a "LAWN MOWER" oil! specially formulated for your lawn mower......HMMMMM, I gotta hand it to'em on that one....

why piss around. just use yamalube.