Police on motorcycle stand/sit behind tree near Shocknow(sp) museum driveway with radar gun pointing toward traffic flowing east. Frequent times are between 7:00-8:30 a.m.. Most affected are morning rush hour drivers taking a back road entrance to Broward Blvd. and who are slightly blinded by the glaring easternly sun. Posted speed limit is 30mph-but since street is relatively empty-drivers are usually caught going at least 40mph.