Let's talk about gasoline. Octane is a measure of one specific property of gas. That is: how slowly it burns. Gas does not explode instantaneously. Rather, it burns at a controlled rate. To accommodate this property, the burn has to start before TDC to make use of the power potential. This is why you have spark advance. The spark starts the burn at a predetermined distance before TDC, based on piston speed as well as compression. The higher the piston speed the more advance needed. This is why the the advance is variable. For starting and idle (low RPM) there is less advance. At high speeds spark advances for more lead time. Octane has nothing to do with any other property of gas. 87 octane and 91 octane from the same manufacturer have the same detergent and stabilization properties. They just burn at a different rate. Enfields generally run great on low octane fuel, especially in a relatively stock state of tune. Unless you you have a built, high compression engine, you shouldn't need premium. If you do, then most likely your timing is advanced for your engine.
UncleErnie is right. Everyone has their pet oil belief. I, too, am an oil snob. That being said, let me state: ANYTHING wet and slimy will work. To get better lubrication you first need to discuss viscosity. This is a measure of how fast the oil pours through a specific size hole at a specific temperature over a specific time. It is not a lubricity measure. Modern oils are the delivery medium for the additives. Viscosity tells you how it will distribute throughout the engine at different temperatures. Multi-viscosity oils have synthetic additives that activate under different pressures and temperatures so as to ensure circulation under a wider variation of conditions than a single viscosity can manage. A 20W50 generally uses a 30W base, with an additive package to enable a portion of it to flow at the same rate as a 20W when cold, and as a 50W when warm. A 10 or 15W40 is usually a 20W base with the additive package.
Now, once you have decided on the delivery package (viscosity) you have to determine other special needs of your engine. A modern engine with tight tolerances needs oil with the ability to flow in tiny spaces. This is usually accompanied by high oil pressures. Synthetics, with the property of being able to be precisely formulated, can be a real benefit in these conditions. Keep in mind, multi-viscosity oils, because of the synthetic additives , are semi-synthetic, even if the base is petroleum. Looser, older style engines often do not utilize a lot of the properties of a full synthetic.
Additionally, you should consider the transmission and clutch. In the new C5/G5 unit construction engines the oil must lubricate these also. Consider that in your car you use a different oil in your engine, transmission (think fiber clutch plates), and rear
end (think gears). Oils for unit construction engines accommodate all three conditions of use. In non-unit engines, particularly older style, lower oil pressure units, the same additives that cushion gears also cushion the greater tolerances.
This is why I always recommend a premium, motorcycle specific oil. You can double the life of your engine, maybe more, with the right oil. Anything will work, but some work better than others. I never go cheap on oil. I even use these same oils in my truck and van.
Topic: Premium Gas ? (Read 8102 times)