I don't even have a cross bike (yet); haven'tt raced any bike discipline; but did do a training session last year on my MTB and want to give it a go this fall.

My questions are ones of race logistics. It may sound stupid; but how does one abandon? Just walk off the course, tell officials, other? I ask because I don't anticipate having a second wheelset; if I flat, I figure my race is over. Also, when lapped do you just keep going, or are you DNF'd?