Radar accuracy question.

Finfan · #1 (**permalink**) 09-09-2008, 01:43 PM

In Tucson it is illegal to exceed 20 mph on a MB. Has anybody ever done a study to determine how accurate a radar gun is on a person riding a bicycle? It seems to me that it would be difficult to register a speed due to all of the irregular surfaces, organic matter (rider), and lack of surface area.

**fairracing31** · #2 (**permalink**) 09-09-2008, 01:57 PM

Hmmm, dont no but that is a very intresting question....I'll look into it when I have some time.

**fairracing31** · #3 (**permalink**) 09-09-2008, 02:32 PM

I looked...all they say is most radar guns are off by plus/minus 2mph

I've got a buddy who is a AZ DPS officer, when I get a chance I'll ask him what he thinks about it.

HoughMade · #4 (**permalink**) 09-09-2008, 04:11 PM

The size and the shape will affect the distance at which the radar will produce a reading- smaller and less reflective- it must be closer. However, if it can get a reading, it is generally accurate.

jasonh · #5 (**permalink**) 09-09-2008, 05:22 PM

I've noticed when I go by the "your speed is" speed limit signs, I have to get fairly close to get a reading. Of course usually the reading I get is the car half a block behind me lol. (I know this because I can't go 40 in a 35. 25 maybe...)

CalgarysFool · #6 (**permalink**) 09-09-2008, 05:56 PM

Is that 20mph by motor alone? Does it make a difference worth quibbling about if you argue that you were peddling?

Reason I ask is that here in Alberta, the statue says somethign like the bike is not capable of exceeding a speed of 30 km per hour with in 2 kms, from a standing stop. Or something like that. Essentially, the restriction is on what the motor can do for the bike. If pedaling along with the motor, I assume, then only the speed limit becomes the limiting factor.

Brenton

**fairracing31** · #7 (**permalink**) 09-09-2008, 06:59 PM

Quote:

Originally Posted by CalgarysFool

Is that 20mph by motor alone? Does it make a difference worth quibbling about if you argue that you were peddling?

Reason I ask is that here in Alberta, the statue says somethign like the bike is not capable of exceeding a speed of 30 km per hour with in 2 kms, from a standing stop. Or something like that. Essentially, the restriction is on what the motor can do for the bike. If pedaling along with the motor, I assume, then only the speed limit becomes the limiting factor.

Brenton

I got stopped for pedaling my motorized bicycle at 23mph. I forgot to tighten my tensioner and it came off and I lost the nuts so my chain would not stay on.

According to the officer who pulled my over, even if I do not use the motor I have to stay with the 20mph speed limit because once you mount the motor on your bike, its a motorized bicycle and you have to obey the motorized bicycle law.

I look at it this way:

If I am in a car and going down a step hill and pop it into neutral and shut the motor off, and the speed limit is 25mph and I am doing 30 mph....I am still speeding.