"Makin' Hot-Rodding Honest"
This is the interview that explains how dynojet created inflated horsepower figures.
by Jeff Hartman

PDF of Makin Hot Rodding Honest

a V MAX.
All of the motorcycle magazine's hp numbers are based on a guy's marketing scheme.
You mean that a lot of non-dynojet dynos had to install "dynojet inflation channels" to read higher than True hp? Yes. Almost everybody wants a high reading dyno.
And that's why some emulated "dj numbers" are so high? (and they know about it)
And not one USA mc magazine has printed that yet??


Wow. This is one of the most telling articles I've seen, lately....
Sports Car International, hmmm........ Shot them an email and no response.

 Finally, on page 3  - the made up dj power figures explained. Funny they should use "Honest" in the title.......

So - the accepted dealership HP scale is the scale based on an inflated marketing claim by Yamaha on a super strong, sleeper V Max and dj didn't know that the Japanese generally add 14.6% t the observed crank reading and that was compared to the actual rear wheel hp... and he didn't like what the real number was, so he inflated it to 120, from the actual 90.

And now, the magazines are scammed into believing it's "correct" and will only accept inflated hp numbers in their magazines - and no longer the real, True HP numbers.

Since then, a dj dyno does not = Superflow does not = Fuchs does not = any other dyno that tries to clone a djhp number. Thanks a lot, dynojet.

True HP = no BS


 It's almost ridiculous to see Factory Pro as, instead of the #1 choice of AMA carburetion that they were, that we somehow, according to the article, were the placers of full page magazine ads and nothing we did worked!!! Wow!! From what I remember, it was more like he got caught at Daytona sticking his dyno's temperature probe against the engine when he tested his own carb kits against the HRC and and our Factory Pro carb kits to get a really high SAE correction factor and almost getting into a fistfight with a racer who caught him doing it.
As far as full page magazine ads? That's an absolute fiction. Never, never, never did either Factory Pro OR Dynojet ever do a full page ad in a glossy periodical magazine!

I guess that you'd have to talk to Muzzy, Vance and Hines, American Honda and Yoshimura race teams and ask them......... Most of them used our carb parts at one time or another.

I wrote a letter to the editor pointing out some facts and am holding my breath that t gets printed!
(April 2006, still waiting....)
(And another letter Dec 2007 and still waiting.....)