What is Superbike?
1.
A Superbike is a motorcycle used for racing in the "American Motorcycle Assosiation Superbike Challenge".
Spelled with a lowercase 's' it refers to the consumer version of the racing motorcycle.
Yes, the competing manufacturers actualy produce the racing machines to sell to consumers (equiped with turn signals for street use).
You could say that, advertising a company name through racing is profitable but,
selling the actual racing bike is more profitable.
Suzuki GSXR
Kawasaki ZX-R
Honda CBR
Yamaha FZR
2.
A hybrid street motorcycle that is highly modified particulary for use racing. This term has been around since circa 1969 and Webster has failed to publish it.
I watched World Superbike racing last night on the Speed channel
See