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When your Harley makes its power in the orange band
you're in "fun to ride" territory.

Are you like a lot of motorcycle owners, paying close attention to maximum horsepower and torque numbers from competing aftermarket tuners and suppliers?

If so, there are a couple of things you should be aware of when comparing the specs. They come down to the “fun to ride” factor.

In my 25 years of experience working with Harleys, I’ve found the most power available from a street Harley running unleaded gas has worked out to about “one per.” What I mean by “one per” is one horsepower and one foot pound of torque per cubic inch of engine displacement.

When you think about it, that’s pretty good. Especially when that power is made without sacrificing low-end performance and engine life expectancy.

If your Harley engine is tuned right, you end up with a bike that’s both fast and “streetable”—in other words, fun to ride!

But that bike won’t necessarily put out the highest HP and torque numbers.

Simply put, you can’t get performance at both ends of the power spectrum. Low end power, low end torque—that’s what your Harley engine was designed to produce. Why? Because that’s the kind of power that counts in real-world riding—pulling away from stop lights, hauling a passenger, passing a car at 60 MPH in top gear.

Take away that torque and you destroy your Hog’s “fun to ride” factor. But that's what you have to do to get those "high end" numbers.

Maximum horsepower ratings sell tuning and aftermarket stuff. So, for many years companies specializing in high-performance products built engines specifically for the Dyno, tuned for maximum HP and little else, just to brag about higher HP numbers.

What the high-horsepower advertisements don’t tell you is exactly how they got their figures. Usually, the methods used eliminate all the fun-to-ride factor, if the test bike is streetable at all!

Examples of HP-increasing tricks that are misleading or make a bike no fun to ride:

  • Using cam timing that is not acceptable for pump gas or street use

  • Installing high-compression pistons that require 104-octane racing gasoline

  • "Calibrating" the Dyno unit to “compensate” for “weather” or “altitude” to produce artificially high horsepower readouts

Your Harley’s gotta run on pump gas, and you want it to have some grunt when you’re pulling away from the lights. So don’t be mislead by the advertisements you read in the magazines. Most high performance companies place those ads to get your money, not for their credibility.

Our philosophy at FLO Headworks it to improve the characteristics that are inherently designed into the H-D engine: fantastic torque and lots of real-world power.

Starting at 2000 rpm on the Dyno curve, our Super Port Flow can give you more real-world horsepower and foot pounds of torque per cubic inch of engine displacement than any other high-performance modification. The focus is on the potential improvement on the lower RPM range where the Harley-Davidson engine was designed to perform.

To quote the owner of our first TC88 R&D project bike, “I can pull the front wheel off the ground at 70 mph in third gear!” Now that’s “Fun to Ride!”

For tuning advice about your Harley-Davidson, call the FLO Headworks customer service hotline, 805-481-6300, or e-mail Perry at [email protected].


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FLO Headworks, 1150 Pike Lane, #2, Oceano, CA, 93445.
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