rules, 'must have 500cc or over'
Just shows how perceptions change.
Me & my friends used to think a 'big bike' was a 750 Bonny or 850 Norton.
Then I had a friend who got an Ironhead XL1000 (this was in the early 80's) & that seemed even bigger than all the others we were used to. Another guy got one of those early Suzuki thingees (1000 or 1100, GS or something?) & that seemed huge too, back then.
Nowadays, well...just look at the Triumph Rocket etc