Aftermarket Exhausts

[JP]

The correction factors are there to relate everything back to a standard i.e. sea level barometric pressure, 20 degrees C and relative humidity. This way you are able to do a dyno run on a dry 30 degree degree day and directly compare the results to those taken on a 10 degree wet day. The figures are corrected to the standard. Unfortunately the industry standard as far as horsepower figures are concerned is the Dynojet inertia dyno (I hate calling those things dynos) so everone, even those with eddie current units have to multiply their figures by 17.6% to give Dynojet horsepower. There will always be discrepincies between dynos even those made by the same manufacturer. The important thing is that their results are repeatable and that you stick to using the same dyno. The end figure gives you bragging rights but the most important thing is you see an improvement after each mod.
The dyno that Volvi's bike was tested on measures about 10 horsepower lower than some others. This is not a bad thing if you only compare the horsepower outputs of bikes tested on this dyno.
The latest dynos automatically correct for atmospheric conditions however the most common mistake made by dyno operators is to leave the temerature probe hanging on the side of the computer, away from any cooling air stream. It therefore correct for a higher temperature than the temperature of the air going into the airbox - result - instant horsepower increase.
The eddie current dyno in Perth is obviously reading true rear wheel horsepower not corrected "Dynojets".