Why wouldn't octane rules apply to motorcyle engines? They're connecting rod internal combustion engines. You think the engine cares if it's in a bike frame vs. a car frame? It has no idea!

Most people advance their timing at the track which requires more octane to keep from knocking. Plus, when you're running on the street, you're rarely at WOT so the high RPM pinging isn't ever present (unless you're a ricer). At the track, you're running at WOT constantly and putting the engine under full load... when it'll most likely ping.

Yeah, you can hear pinging on the Harley. The rear head is under my balls! If that thing sounds remotely like it could blow up I pay attention! Believe it or not, due to the super long length of my pipes, the bike is considerably quiet while riding. It's the people behind me who get wide open header terror

FYI, I run 93 octane in the Harley even though it's like 8.5:1 compression. It has a 34 degree timing advance, so anything lower knocks. In my Chevy I run 87 octane on a 8.1:1 compression with a 8 degree base timing and can run WOT all day without a ping.