Are Vipers invisible to stop light sensors?

[Jay M]

There is one particular stop light in my area that doesn't appear to see me when I'm in the viper. It's a left turn lane. the first time, the lights went through a full cycle and I never got the green arrow until there were cars behind me. The second time, I waited for about 5 minutes, there wasn't a car in sight so I went ahead and turned.

A friend of mine who lives on that street affirmed that she never has to wait more than a few seconds for the arrow at night.

Has anyone else experienced this?

~Jay

 

[Ratical2]

I found a couple of places that don't trigger the same when driving my Viper vs my other cars. These were also the same places that never saw (electrically) my 500lb motorcycle. My guess is the system sensitivity is incorrectly adjusted.

 

[RobZilla]

You are too far up to the stop line. The sensor needs all 4 wheels in the box to sense the vehicle.

 

[commandomatt]

You are too far up to the stop line. The sensor needs all 4 wheels in the box to sense the vehicle.

..so 'ratical 2'....you need to install a second pair of wheels on your motorcyle to trigger the light !

Matt

 

[eucharistos]

some say it is the aluminum block and composite body

 

[eucharistos]

How to Trigger Green Traffic Lights - wikiHow

Understand how "demand-actuated" traffic signals work. These are traffic lights that will only turn green when a vehicle is sensed, usually to allow the vehicle to cross a street or make a left turn. At problematic traffic lights, look for a loop of wire buried in the pavement of the road near the stop line. This is called an "inductive-loop traffic detector"[2] that works somewhat like a metal detector, sensing any ferrous metal (steel, iron, etc.). Sometimes these sensors are improperly designed or adjusted, so they don't pick up on the presence of a smaller vehicle. These sensors do not detect the weight of a vehicle, but rather sense how much it disturbs an electromagnetic field. Once tripped, the signal will begin the light switching process using pre-programmed rules (within 30 seconds, usually less). "Bigger" or more noticable vehicles do not cause the light to turn quicker - your vehicle either trips the switch to begin the process or not. There are ways to make yourself more noticeable to prevent waiting indefinitely.

 

[Ratical2]

some say it is the aluminum block and composite body

Thanks for description. It was what I was alluding too. The motorcycle was mostly aluminum, with a steel or chrome-moly frame. Not enough ferrous metal to force current through the inductive loop.

I assume that this is the problem with the Viper as well. If the sensitivity or trigger current is set to high the car is invisible.

I played with the idea of mounting a couple of super strong magnets on my frame rails of the motorcycle to see if I could improve the trigger rate, but my idea never got off the drawing board and now the motorcycle is gone.

 

[Mopar Boy]

Try this:

When you are sitting at the light, in the magnetic pick up area, rev the motor to about 2-3000 and hold it there for 5-10 sec (depending on programmed light pickup delay).

Betcha it works.

Why?

Your revving allows the alternator to build a charge as it is spinning faster, thus creating a larger electromagnetic field than at idle. The sensor now picks it up.

 

[Martin]

When I rode a lot, I had that problem, too. The easiest thing to do is just jump out/off and press the crosswalk button (if there is one). That will get the traffic light timing system to cycle fast. Otherwise, wait a reasonable amount of time, look for traffic and cops, and go when safe.

 

[shine]

It drives me insane when I see people (particularly out-of-towners from little towns) pull up past the thick white line (where you're supposed to not cross) all the way up to the far crosswalk line -- which not only blocks the crosswalk for pedestrians, but also puts you outside the trigger box. Then the light never triggers, and you see people get really mad.

I've seen people finally realize it after they miss 3 or 4 light cycles, and try to back up, after traffic has already built up behind them. I've also seen them just run the red light.