What exactly IS the difference between 4 stroke oil and car

[buymore]

ok now....the Castrol 15w-40 I am using currently says for "gasoline and diesel engines" and the grading is ok also. It has grading above and beyond what is required on the stickers and owners book for my Roketa DB05. It's only a couple of bucks, I'm just going to change it! Better safe than sorry! I've only put about two hours on this oil at most!

[Beerslayer]

The Castrol 20-50 4 stroke motorcycle oil is not expensive and it meets the SG and SH specifications. The additive formulations are a bit different for automobiles. The automotive oil is probably fine for the engine, but there is that wet clutch thing. Just my opinion. Worth what it cost you.

[30-Arider]

Originally Posted by Ferrit

What Liverchip and Buymore are referring to are some of the newer oils that contain "friction enhancers". These are usually a type of moly-d or other super slick compound. This is one of the reasons that you are seeing more motorcycle specific oils as they will definitely NOT have these friction modifiers in them whereas an automotive oil may or may not. Usually a quick read of the label will reveal if these compounds are included. Sometimes the oil is marketed as "high mileage" or "increased gas mileage" oils.

Having grown up and retired from military aviation I am a firm believer in oil analysis. Our local Shaefer Oil rep does samples rather cheaply (doesn't hurt that I buy oil from him in 30 gal drums). Based on past experiences I'm planning on changing the full synthetic oil that I run every 2500 miles or so. If I ran dino oil I would change it every 1000 miles or so. I routinely run my car for 10-12k miles between oil changes.

Question for you: In any air combustion engine you are not going to have 100 effieciency. You are gonna have combusted material pass the rings. This material passing the rings is primarily gasoline. gasonline is not a good lubricant and thins oil out dramatically. This is typically what causes lots of the color change in oil....essentially thge oil is polluted. Dont you think going 2500 miles on one quart of synthetic oil in a single cylinder air combustion engineis a little too long...or worse yet 10-12 K miles on any other motor?

Quick story: When I worked for Coopers Cucle Ranch and Mount Holley honda Yamaha I had an Amsoil salesman come in all the time trying to sell me on carrying thie product. This guy had a new 1/2 Chevrolet conversion van. He bragged to me how he had 23,000 miles on the current Amsoil motor oil in his truck. I asked if I could check his dipstick and it was burnt black. Told him good luck with it. He bragged how he only needed oil changes every 25,000 miles. He changed his oil, and then 3K miles later he lost 2 mains and 3 rod bearings. Chevrolet did not honor thier 36K mile warranty for the reason on "No maintenance".

Amsoil and synthetics are great products...but even though they lubrucate better...that doesnt mean they dont get contaminated just as fast.

[jkomp316]

I found some cheap ATV oil at Fleet Farm. Its like $2.89 qt. Says it has NO friction modifiers, and its good for wet clutch applications. 10w40 or 20w50

Most car oils have friction modifiers, which will make the clutch slip easier, thus wearing out faster. Im not sure if our whopping 14ft lbs of tourqe would matter much though.

[katoranger]

Use the fleet farm oil. It is probably good stuff. I am using up some walmart oil I had. Just going to run about 200 miles then change it again.

I have a partial quart of valvoline 4-stroke oil that I will use next.

Allen