I met the guy that sells these Boss Hoss cycles in Airdrie. Barry is his name.
He personally rides thes bikes all over. He started out with one that had a 380 HP Chevy 5.7 Liter in it. He teh got ahold of one with the Chevy 502 big block V-8 with over 500 HP.
I asked Barry if the 502 was any better than the "already oversize 5.7 Liter engine.
Barry said that once he had the 502 with 500HP, there was no turning back to a 380 HP 5.7 Liter.
Personally, I think any guy must be off his nut with 380 HP in ANY bike.

1700cc is just right, lots of power, but not so big you can't use the available power to weight ratio in your favor.

I don't care what a 502 V-8 is put into, there's no way you'd make 17 mpg on a good day... there's just too many cubic inches to keep fire in the cylinders without using lots of fuel.

Internal Combustion gasoline engines require 1 part gasoline to 14.7 parts of air to rum properly.

But I guess, it's aneat toy if it turns your crank!