In The 2 Past Issues... 
We've seen that 2 of the factory superbikes have got some serious problems !! 

Both of these bikes have aerodynamic problems caused by the direction their exhaust is pointing. The Harley points it's exhaust up, and the Kawasaki is it pointing up and to the right... 

	What's the best way to point the exhaust ?? Here's an interesting photo of the correct 5 degree pipe angle  (Featuring Schmidtastic's famous passenger.... )
	The Idea The main idea is that if you project back about 20 ft. / 6 Meters  the exhaust should point to the exact center of the aerodynamic form. In the last issue we learned that this affects the  "Dynamic Aerodynamics"  or how the aerodynamics are affected when the bike is moving with the engine running.  This issue is all about: "Dynamic Horsepower" Which is: "The Closely Related Problem" I've been asking about ... !!

More "Invisible" Power Loss !!
                

Q: Where does the energy that's being used to enlarge & deform 
the Harley's aerodynamic form come from ??

A: The Engine !!

Just as the exhaust is disrupting the bike's aerodynamics, the aerodynamics problem is costing the engine real horsepower !!!

Since the engine is an air pump, it's using an amazing amount of energy to de-form the aerodynamic wake behind it. The piston has to push the exhaust out against the natural flow of air behind the moving bike. 

This is Another Example of Why Speed 
Isn't Directly Connected to Dyno Readings

The Harley & Kawasaki superbikes may make "X" amount of power on a dyno, yet their actual 
Dynamic Power is progressively reduced as they reach top speed on the racetrack. 
In the real world, Dynamic Power is all that matters...  (unless you're just "bench racing"...)     :)

  
Another Way of Thinking About It ...

Ram Air Induction helps an engine make more  horsepower as it increases it's speed, by forcing positive air pressure into the engine. 

At the back of the bike, when the exhaust is pointing the wrong direction, the engine will make less  power as it increases speed !! 
It's a type of "Reverse Ram Air"

Taking It One Step Further:

By purposely pointing the exhaust gasses exactly  into the center of the aerodynamic draft created by the bike, the exhaust will be sucked out, and the engine doesn't have to work as hard.
It's "free" power.

That's Right .... Now even Britney Spears   knows how to FIX Eric Bostrom's Power Problem... All she has to do is: Loosen 1 bolt, turn the silencer 5 degrees, and re-tighten the bolt !!

Breaking News: Harley's Quitting Superbike Racing in 2002 ???

Harley Engineers: Don't Give Up !! 
Just Take A Little Break, Keep Reading Power News, and Before Long, You'll Be Ready To Win !!
All the horsepower secrets you'll need to easily win are contained in the upcoming issues !!

Have a Cool Day Everyone !!
~ MotoMan

Next Article: The 8 Phase Motor !

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