Classes can be found on the race page that has already been posted above. Most people start out in Cat3 (Novice), but some go straight to Cat2 (Sport). That all depends on your physical ability (aka, did you come from road riding...)
Yes, you will be assigned a number and a chip for timing.
Standard attire is whatever you feel comfortable riding your bike in. Required attire is a HELMET.
No, we do not drink beer in this club. Beer is the devil. --->