Yeah, not many Mopeds out in that part of the county that I know of. You would probably have to transport your ped to south city, It's about 25 miles away. Wednesday night rides meet at the kings-highway skate park around 7:30-8pm.
I'm out in St. Charles, about 15-20 miles from Bridgeton but you would definitely have to transport the ped to get across the Missouri river. The Holy Rollers have a ride every other Sunday out in 'Ofallon, just a little west of St. Charles