From a press release issued by Lou Cariffe:

St.Louis SuperMoto Round Cancelled

The cancellation of the SB2 Supermoto National Championship series has led Clear Channel Communications and Cariffe Promotions to suspend their event scheduled for September 6th and 7th of this year.

The promoters have said that they are deeply disappointed by this development and that they plan to reschedule a stand-alone event as soon as certain details are finalized.