*Sighs* I miss my father.

Sorry, he was a truck driver and I could have gotten some info on him on this.
Anyhow, on topic. Diesel is safer in military situations than petrol, and has been for a long time. (They called early, Petrol-Burning tanks "Ronsons", IIRC: "They light up the first time, every time.").
Most vehicles you're going to want to tank on any long trips, including motorcycles, will probably have the Multifuel Engine modification. I'd highly suggest it, at the very least. Due to both VITAS Plagues, most places in the world are like Northern Canada today, fifteen billion miles of
*NOTHING*. When it's two towns until the next petrochem station, buying a few gallons from the local moonshiner can come in damned handy. As a lot of vehicles are also hybrid vehicles, the Sun Cell modification and driving on the electric motor is also a good suggestion, with some camping gear and rations to wait while the system charges up. If I were making gear, I'd probably have some kind of military-surplus "Solar Panel Blanket" you could spread out and do the same thing without the modification. But that's me.