How many projects begin this way? You see something that looks cool and think, "I bet I could build one of those" and next thing you know you're making sketches. Steve, a motorcyclist from Melbourne, Australia, watched a motorcycle dyno shootout and figured he could build his own dynamometer, how hard could it be? Well, it took him 3 years but he did it, he finally had his own homebuilt motorcycle dyno.
When I say he built his dyno, I really mean that. He wrote the software in Visual Basic, used a Basic Stamp microcontroller so the software could communicate with the hardware creating the data acquisition unit, had the drum built to his specs, put together a trailer to hold the whole setup and learned enough rotational physics to make the whole thing work.
The dyno he built is an intertia dynamometer, which means it's the more common type where a drum is accelerated by the motorcycle's rear wheel. When you record how fast the drum is accelerated through the rpm range, a measure of torque, you now have both torque and rpm throughout the range. With those two numbers you can calculate the horsepower at each point.
A very cool project overall, I like it.
Thanks for the tip, Andy!