Speed traps are places the Davis Police/Highway Patrol set up multiple car/motorcycle officers to increase revenue for the city/state. Most motorcycle cops and some highway patrol officers can be seen with Lidar whereas cruisers more frequently use radar and "pace" vehicles.
MACE BOULEVARD CURVE/EAST COVELL Heavily enforced. A Davis PD cruiser cop will camp out behind the bushes and nab speeders coming around the curve. It's usually desolate so it's easy to lose track of your speed and them to pounce on you. Be extra careful during school hours when the speed limit jumps from 40-25.
ANDERSON ROAD Usually weekdays during school hours. A Davis PD motorcycle cop will tuck between two cars on the opposite side of the elementary school while school is in session. Be careful racing to beat the yellow lights, violating the loading zone policies, and pulling out in front of bicyclists. Speeding usually isn't an issue since there's so much traffic but bet he's watching.
ANDERSON ROAD (2) Rarely enforced. Ocassionaly the same motorcycle cop who was nabbing alleged violators during school hours will move towards West Covell across the street from the Save Mart during random off commute hours. He usually isn't hiding and has his lidar unit pointed straight at traffic. Be aware lidar is relatively accurate for long distances so he'll probably clock you before you even see him... which is probably why he isn't hiding.
RUSSELL BOULEVARD Mostly at the way hours of night on the weekends. Usually just rolling around by the fraternities looking for drunk drivers and disorderly conduct. When the pedestrian signal lights up, make sure you stop.
INTERSTATE 80 BUSINESS EAST Often enough. A CHP cruiser is usually camping out behind the underpasses right after the causeway. DO NOT BE FOOLED IF THEY ARE FACING THE SAME WAY AS TRAFFIC. They know most people tend to gun it when the 3 lane traffic on the overpass opens up going to Reno or downtown Sac. Best to stay in the right lanes and set the cruise control to 70 until you get beyond all of the overpasses.
INTERSTATE 80 WEST Mostly weekends. If you're ever venturing to San Francisco, Fairfield, Vacaville, etc be aware of the CHP motorcycle officers camping out just past Dixon.
General notes on the CHP - watch out for them merging onto the freeways behind you. This is where most people usually fall victim to "pacing". He'll get in a far off lane some determined distance behind you and follow you while he looks at his speedometer. Easy money since you probably never saw him get on the freeway. Something to be aware of.
INTERSTATE 80 EAST Random but often. Dropping down the east side of the Sacramento River bridge, it's easy to pick up 5-10 mph and there's often a cruiser waiting to take advantage of that. The fact that the CHP academy is only a couple miles way doesn't help. Also be aware that there's usually a heavy enforcement action every weekend further up 80 just past Madison Ave extending to the CHP weight station involving radar and multiple cruisers.