Ord 3973 works. Everytime it happens, pick up the phone and call.
Keep a log in a spiral notebook that includes the incident report ##
(the dispatcher will give it to you if you ask when you make the complaint) Keep an accurate account that includes time, date,# of riders, what kind of vehicle ect ect.....avoid talking to the parents at this point, you will only risk an angry confrontation from the perpetrators.
If the behavior persists, you can take your neighbor to small claims court for maintaining a nuisence. I believe the max amount is $5000 per plaintif.
Usually, a couple of visits by the San Bernardino County officials is more than enough to get the message across.
If there is ANY retaliation, report it and include it in your log.
Good luck Mr Wizard