A simple compression test will suffice. Gauge and extension to fit down the spark plug tunnel are less than $50. If a cylinder is low, you can have a leak-down test performed. Usually a valve will go before the rings, and you can bring the head to a shop, or send it out for service.
A stock busa is around 160hp. But how does the dyno operator know that a spark plug isn't fouled, fuel filter clogged, the tire slipping, or a dozen other things wrong? If he had it checked in Denver, he'd be lucky to hit 150 at this altitude.