What's the difference btwn Arenacross & Supercross

Primarily the distance and width of each section. Arenacross is very tight. The races are generally held in Hockey arenas ... whereas Supercross is held in Football stadiums. That alone should give you a clue as to the relative size of the tracks. Supercross speeds are much faster. Arenacross tracks are also much more alike from race to race than are Supercross tracks. Much less variation in track design.

Anyone else want to pipe in?

Arenacross = Motocross in a fishbowl.

Or.......Sonic the Hedgehog in a habitrail!

Cool stuff.

And since it's sort of a "minor league" the riders tend to be hungirer and more agressive. Tight tracks with agressive ridrers = fun to watch.
P.S. the arenacrossers also race for two days and in both 125 and 250 classes, and then there is an amatuer day on Sunday, very few supercrosses do the amatuer day thing. (O.K. with me those jumps are HUGE!!!);)

Most of the riders ride both 125 and 250 races. I believe that the points are totalled from both of the classes for the total points race. Plus, there are 5 motos per class, 2 heat races, semi final, LCQ and the main. So there are 10 motos plus a dash for cash race in which the riders are racing for money that is donated by the fans. Ususally each city has two nights of racing.

I personally love Arenacross. It is more smashmouth than SX. Nearly every moto has at least one wicked block pass resulting in a wreck or two. Nothing at all against the SX guys but those AX riders are tough. Imagine running 4-5+ motos in a night two nights in a row.