I don't have any useful info for you- like why they're racing, how far the race was, or where exactly the contestants rode to, but I DO know that the winner gets a new bike.
I only stayed long enough to watch them get started because it was quite hot out there in the sun and I'm not feeling too great (either because of the drinking I did this past week while my friends were in town, or because I've been in a funk for over 2 months) but I think I saw pretty much everything I needed to see.
Even though I buggered off, I happened to be on Front Street when the winner came down the final stretch:
All in all, I found this event pretty UNeventful- even the few people that I talked to were disappointed in the turn out.
Where's the love, San Pedro?