Salute from a motorsport (Isle of Man TT, MGP, bike and car, etc) marshal and rally Stage Commander!   
<S> back...  
I won't work bike events.  They seem to fly at least one person out each bike event.  I am surprised they don't have a bird on the ground staged and ready to go.  
I work mostly smaller events for local clubs (SCCA, NASA, Porsche club, etc), but I have worked a few pro events.  Of course I say smaller, but SCCA gets about 700 competitors for their end of year championship.