Credit: William Cummings, United States
Thanks for the information! In order to update this on IMDb, go to the page for The Born Losers (1967) and click ‘Edit Page’ at the bottom. Then select the data area you wish to correct from the list of options on the next screen.
IMDb does currently list in the trivia section that the biker’s lair location was filmed at a property once owned by Rudolph Valentino. Wikipedia notes the bikers’ lair being in Playa del Rey in a property owned by silent film star Mae Murray.