My mate said the same thing when we rode to Yea... Caught up to him after he'd been stopped for ~10 minutes...
As for 250's being quicker due to lightness, unlikely.. Unless it's am experienced rider on the 250 and a noob on the big bike... I was topping out at 150 on the straights while they did 150 through the bends..
Bigger tires, bigger brakes, more power etc etc