Engine oil

[Fazerider]

Lubricant manufacturers do themselves no favours by letting the marketing men provide the descriptions for oil. Being non-scientists they naturally have nothing to offer but hype and bullshit when hard facts and a detailed listing of the additive package would go a long way to earning trust.
However, it's pretty obvious that oil in your bike engine has a harder time than it would in Ford Ka. Aside from wet clutch requirements, the power per cc of cylinder displacement is greater than that of a Mclaren F1 and the oil is shared with the gearbox which in a car is typically filled with oil of far higher viscosity.
So, if you're happy to buy the cheapest 10W-40 that you can find in Asda for your bike, and are convinced that motorcycle oil is just car oil with the word "motorcycle" on the packaging you might wonder why oil companies provide oil of unnecessarily high quality for under-stressed engines.


Simon.Pieman/VNA: I have used car oil (and not the cheapest) in bikes and regretted it… not that the engine actually broke as a result, but power gradually dropped off as the cam lobes suffered excessive wear.