Originally Posted by VN750Rider/Jerry
All radar and laser speed devices do work on motorcycles. But, it is not totally accurate, and operator error will make it more inaccurate. Radar can be made more accurate than it is, believe it or not, when they clock the speed of a baseball in a major league game, they try a lot harder to get it right than the cops do.
I have worked for the City of Chandler for 34 years, know a number of cops, and they explained it to me. Because of the error inherent in radar and laser systems, they set the speed at which they will stop you several MPH above the speed limit. A good estimate from the cops themselves however, is that only about 70% of those ticketed for speeding by the use of radar are actually guilty.
As for just how sensitive radar is, I can tell you that a person on a bicycle will trip the "photo radar" vans they set up along the streets. I've done it. Jerry.
I can't speak for the city of Chandler, but I was a cop and ran radar, both hand held and mounted, for fifteen years.
Our radar was accurate to 1 mph. Radar is better than that, but you can't write a ticket for .1 or .5 mph over the limit. We allowed five mph because
1. The auto might only be accurate to plus or minus 3mph.
2. it was traditional among departments.
3. An elected judge could not be expected to hold a motorist to the exact letter of the law...the intent of the motorist is important to the judge.
Rain or fog do not diminish the accuracy of radar, only its range.
Some radars can be aimed with great accuracy, but the users manual required only (I think) a 10 degree or less angle of projection on those radars I was trained on.
Viewed in one dimension (like a picture on a magazine) a tractor trailer say, 300 feet away is larger than a motorcycle 100 feet away, and the radar will see that larger target, or if it knows there are two targets, will not give a reading for either. This is a safety built into the computer to prevent mistakes of identity.
Radar will give a spurious reading on several different occasions. It can read around corners if the signal is reflected off a shiny sign or plate glass window. If the signal received is from a neon light rather than the return radar signal. (If the hand held radar is pointed at an electric motor such as the police car's heater. my Crown Vic heater could be read as 25 mph,45 mph, or 65 mph, if I remember correctly, then locked in and pointed at whoever).
More important than the accuracy of the radar unit is the consistent use of it by the officer. There is a specific number of tasks he must go through between radar uses that assure the court that he is using and calibrating it properly. When a ticket is beaten in court it is usually because the defense convinced the court or the jury either that the officer did not follow these proceedures or that his word can not be accepted.
As for the Ohio ruling, it is possible that the press reported it accurately, but more likely that they did not. I would not be surprised to discover that there was a narrow definition of when the officer's judgement was sufficient. When I was a cop, it was the opposite. We took pains to say in court that we observed sombody we thought was driving too fast, and only then did we verify it with the radar. The common mistake was to set it to make an alarm if a vehicle was doing, say, ten over, let the radar tell you somebody was speeding, then the officer had to choose who was the offender. That was a recipe for a dismissed charge. By departmental policy we were forbidden to use the pre-set function.
Finally, and not to get in your face, Jerry, but I would say that upwards of 95% of the tickets written by honest, competent officers were accuarate.