Friday September 24, 2004 was the 12 year anniversary of Critical Mass. It also marked a return of Critical Mass to the streets of Santa Cruz. About 30 bikers met at the clock tower and rode around downtown and the westside.

Bikers were generally respectful towards the unfortunate souls rolling around town in metal boxes, however several motor-aided communters were delayed for a short time. The responses were mixed from the people in the cars, but the majority of people, especially ones driving 18 wheelers, were supportive of the Critical Mass.