How modified are the bikes?
The bikes racing on the track here look very similar to the ones you can buy at your local dealership, and that’s done on purpose. Back in 1986, the AMA began enforcing a “production rule,” which requires all race bikes to use the same major components as the bikes sold to the public (frames, transmission/crankcases, and engine cylinders must be the same as production, for example). Beyond that, though, almost anything goes. The top factory race teams spend thousands of dollars reworking engine internals to produce more power. They bolt on high-end front forks and rear shocks, then spend countless hours developing those components to meet rider preferences. Then they bolt on a variety of aluminum, titanium, magnesium, and carbon-fiber parts to make the bike stronger and lighter. The end result is a bike that looks like one anybody could buy but that performs at a much higher level. As always in racing, speed costs money, so the top factory teams generally boast the best equipment.
