Old Dynojet news, but did you know ?

[ohgood]

This is an old article, that anyone can find via google. Just think about all those folks that -know- their bike is making more power, because they dynojet'd it and then ran it on a dynojet thingie:

"One of the biggest headaches of DYNOJET's go-it-alone chassis-dyno project was figuring out how to assign meaningful power numbers in the face of unknown inertia from the moving parts of the hundreds or thousands of engine, driveline and tire combinations. Wrestling to fully understand inertia and powertrain losses, Dobeckand his team quickly realized that the standard physics formula of weight, time, and distance for converting acceleration into horsepower simply didn't work----the derived number was always lower than accepted numbers. They poured on resourses and burned up time and money investigating it, but no matter what they did, the math never added up.
DYNOJET's final number-fudge was arbitrarily based on a number from the most powerful raod-going motorcycle of the time, the '85 1,200cc Yamaha Vmax. The Vmax had 145 advertised factory horsepower, which was far above the raw 90HP number spit out by the formula. Meanwhile, existing aftermarket torque-cell engine dynamometers delivered number that clustered around 120. Always a pragmatist Dobeck finally ordered his chief Engineer to doctor the math so that the DYNOJET 100 measured 120HP for a stock Vmax. And that was that: For once and forever, the power of everything else in the world be relative to the '85 Yamaha Vmax and a fudged imaginary number. Dobeck's engineering staff was dismayed by the decision, but the DYNOJET 100 exclusively measured surplus power available to accelerate the vehicle's mass – no more , no less – and that was true even if the modification was a low inertia flywheel or lightweight wheels."


I'd say it's a whole lot cheaper just to find a dude with an old Vmax and race him. Then you get an idea of what your HP is like

[Kurlon]

Someone's been drinking from the Factory Pro kool-aid stand again haven't they... : )

[The Buddha]

They used to do most dyno tuning in the drag strip in the old days.
They'd fit a pipe on it, run it in the 1/4 mile. Then cut off a sliver off the pipe ... repeat - the time drops a little ... ... till they saw the time drop, drop drop ... and then go back up ... then they know that that last sliver they took off needs to be welded back on.
I jet it the same way ... up up up up till it starts to get worse, and leave it right there ... rather be a shade rich than a shade lean ...

That is the method I call "Trial and terror".
Cool.
Buddha.