Yup, between 4AM and 5:30AM on weekdays. Its about the only time I have to ride during the week. Been doing it for 20 years in two different locations I've lived at here in Southern California. Current location I do laps of about 6.3 mile/10km each on suburban streets with good lighting. Evening (6PM - midnight) and early AM (midnight - 3AM) there are either too many cars or too many drunks on the road (bars close at 1AM).