Here's your mathematical explanation from wikipedia.org for convenience:
Power
The power required to overcome the aerodynamic drag is given by:
Pd+Fd*v=1/2pv^3ACd
Where:
Fd is the force of drag,
p is the density of the fluid,[3]
v is the speed of the object relative to the fluid,
A is the reference area,
Cd is the drag coefficient (a dimensionless parameter, e.g. 0.25 to 0.45 for a car
Note that the power needed to push an object through a fluid increases as the cube of the velocity. A car cruising on a highway at 50 mph (80 km/h) may require only 10 horsepower (7.5 kW) to overcome air drag, but that same car at 100 mph (160 km/h) requires 80 hp (60 kW). With a doubling of speed the drag (force) quadruples per the formula. Exerting four times the force over a fixed distance produces four times as much work. At twice the speed the work (resulting in displacement over a fixed distance) is done twice as fast. Since power is the rate of doing work, four times the work done in half the time requires eight times the power.
End quote.
This is the main reason it's so difficult to achieve 200+ m.p.h. speeds on production motorcycles. A stock unrestricted 'busa with 170 or so rear wheel horsepower is good for ~190 m.p.h., yet it takes an extra 160 horsepower to gain an extra 40 m.p.h.
Figures above taken from here.
Note how very close the mathematical formula and the real world numbers correlate.
From the add I linked to, before it disappears:
"You are bidding on the "Tiger" from Tiger Racing. This bike holds the World Land Speed Record for the Fastest Nitrous Bike in any class at a terminal speed of 228.803MPH. The "Tiger" has been in numerous magazine articles and is world reknown. Buyer should pick-up here in Toledo, OH or come at least within 250 mile radius where I will trailer your winning bike to you without charge. I will include the tune-up in the ECU and Dyno-Jet Power Commander that will allow you to have a turn key solution for going 220+ if you are a skilled LSR rider and weigh less than 200lbs."
And:
"She's 200hp on motor with another 130HP of Nitrous tune-up."
