Fuel In Oil Motorcycle . Oil is added to the fuel in 2-stroke engines. Mineral oil actually helps the rings and pistons bed in properly during the crucial run-in stage.
Fuel Injected and Newer Engines. The main advantage of mineral oils is that they are cheaper sometimes about a quarter of the price of synthetics. The Lucas Oil 10702-PK6 Synthetic 20W-50 Motorcycle Oil is specifically formulated to provide your bikes engine extended lubricant life as well as resistance to hot temperatures.
Vacuum petcocks suck.
It just finds its way past the rings and into the oil. Gasoline is not added to the oil. A leaking gas valve can do more than just waste gasoline. When excess fuel finds its way to the crankcase like in the case of a stuck fuel injector a strong gas smell will pop up.