dogman dan said:
One reason the street bike race has a problem with adding a motor category is the difficulty with determining if a particular bike is street legal. You'd instantly get guys riding home made motorcycles with pedals. Far more trouble than it's worth.
In Arizona (and thus Tucson), as long as the motor is electric (or at least not gasoline/ICE), it can have a million HP and still be street legal, as long as you are not riding faster than 20MPH, and it has 3 wheels or less in contact with the ground, etc. The same speed limit applies to ICE assist, too, but there is a cylinder size limitation of 48cc (though no HP limitation that I recall, so if you could somehow get higher HP out of the tiny cylinder....). The speed limit does not apply to human powered bicycles, however--the only limit is the street's speed limit wherever the rider is riding it, or whatever is "reasonable and prudent" (whichever is less).
http://www.azleg.gov/viewDocument/?docName=http://www.azleg.gov/ars/28/02516.htm
But because of that limitation in speed, any race not on private tracks/land makes any bike that is not fully human powered (with any assist on it of any kind), kinda pointless, as good human racers can certainly go faster than 20MPH for extended periods. Unless it is such a long race that humans would become too exhausted to keep up >20MPH for the entire race, an assisted bike could never win, if ridden legally. (assuming one had enough gasoline or battery power to keep going that long).
If ridden illegally on public streets/roads, the rider could be ticketed and the usual tickets I've read about in reported cases are the big three, no licence, no registration, no insurance, because at that point it's considered by the police to be an uninsured / unregistered motorcycle. They'd probably impound the bike, too, and then the impound fees probably make it cheaper to build or buy a new bike than get the old one back. :/
If the race is not on public roads/streets/highways, but on a private track, then it's a different thing entirely, and the assisted bike with the biggest motor and highest capacity power source and best brakes would probably win, as long as the rider could keep it rubber-side-down.
But regarding engine size for ICE, if road-legal was a requirement for the race, it would require that the riders bring their bikes with the cylinder tops not installed, and a volumetric test or measurement done prior to the race, to ensure that ICE bikes would not be outside the road-legal size.
Electric motors would be more complicated to ensure compliance with any race-specific rules, but cannot have a "road legal" compliance test as there are no laws regarding their size, power, etc., in AZ.
