We hold 2 races a night. The first, which starts at 6:17 pm and is 20 minutes plus a lap (which usually ends up being 30 minutes because our judges are viscious), and the second, which starts around 7:00 pm, is 15 minutes plus a lap. There is about a ten-minute break in between.
The course layout will change every week or so, just to keep things interesting and to make sure the technical guys can whomp the pedalers one week and the mudders get their shot against the roadie transplants and all that.
There will be a shortcut every week, and it's open to everyone but never free and you never know what the toll for taking it will be. (Though it's never money.)
Cyclocross tire seletion
Tire choice is of great importance in cyclo-cross racing. First
of all the use of tubular tires is still very popular, even more
so than in road racing. This is, in part, due to their ability to
be run at low pressure (22-40psi/1.5-2.75bar) without increasing
the risk of pinch flats.
Low pressure is desirable due to increased amount of contact with
the ground giving the tire more "grip". However this increases the
risk of the rim 'bottoming out" on the ground. With clincher tires,
this is a problem since the tube becomes pinched by the rim and
can be cut open causing a catastrophic flat.
On the other hand, with a tubular set up, this is not a problem
as they cannot pinchflat thus the only concern is damage to the
rim. A tubular setup also offers a weight saving over its clincher
counterpart and has the ability to be ridden on if a flat does occur
so a racer can reach the pits for a replacement. -from Wkipedia