World-famous Amoeba Records is hosting a bike-culture party in Hollywood on Sunday, August 17th, from noon to 5pm, featuring food & drinks, music, raffles, and more to help celebrate bike culture in Los Angeles. There will also be workshops and bike valet parking, the latter by the Los Angeles County Bicycle Coalition. One of the party's goals is "raising awareness about the Ride Hollywood campaign, which supports proposed bike lanes on Hollywood Blvd"; bike lanes are always a difficult process in politically-turgid Los Angeles, so this is a big deal.
Just so you won't get lost on the way, here's a link to a map.
You'll find more details on the Amoeba website.