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Discussion Starter #1
I found 2 models of Green Light Triggers in the J.C.Whitney catalog.
They are 1" X 2" X 1/2" No wiring needed to hook up.
Original is 25% more effective than the compretition,
and the HP model is 95% more effective.
Original is $14.99 and HP is $21.99

Has anyone used these types, and if they have are they very effective?
All the small towns around here have crap for lights. I have set at some till another car comes along.
They have passed a law locally this last year that we are allowed to go through a red light if it doesn't turn after a specific time, and there is no other opposing traffic.
Sounds dangerous to me. I plan another route, or wait till another car comes along, unless it's 4:30 AM when I get off work.
 

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Daily rider
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All you need is a rare earth magnet or two. There's a better way to trigger lights, at least the ones where you see cracks in the road where the sensor is. If you pull up to the sensor on either the left or the right - directly over the crack, you will trigger the light as well. It's different for the new style that are under poured concrete and no cracks. I haven't figured out how to trigger those yet.

The stoplight sensors are supposed to detect mass. Since most cars are a ton or more in weight, it's not too difficult to detect that mass. But, since bikes are much smaller in mass - and lighter - they don't trigger it. Rare earth magnets are supposed to fool the sensor into thinking there's a vehicle with more mass over it.
 

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All you need is a rare earth magnet or two. There's a better way to trigger lights, at least the ones where you see cracks in the road where the sensor is. If you pull up to the sensor on either the left or the right - directly over the crack, you will trigger the light as well. It's different for the new style that are under poured concrete and no cracks. I haven't figured out how to trigger those yet.

The stoplight sensors are supposed to detect mass. Since most cars are a ton or more in weight, it's not too difficult to detect that mass. But, since bikes are much smaller in mass - and lighter - they don't trigger it. Rare earth magnets are supposed to fool the sensor into thinking there's a vehicle with more mass over it.
I would add that it is "conductive mass"........
 

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I have a box of very strong hard disk magnets. PM me with address and numbers, I'll send you one. I put one on my kick stand, get to a light, roll over the crease, put your kick stand down on the crease put it back up and it will trigger the light timers, never failed.
 

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I have a box of very strong hard disk magnets. PM me with address and numbers, I'll send you one. I put one on my kick stand, get to a light, roll over the crease, put your kick stand down on the crease put it back up and it will trigger the light timers, never failed.
And I have done that too, but without any magnets and it has worked for me. (The kickstand is solid metal...the sensors are basicly just metal detectors)

The idea of putting powerfull magnets under my bike sounds like a problem waiting to happen....like "standing up" a steel screw or nail so it punctures your tire.


I'd rather just run the light if possible......

KM
 

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I too am a sucker. I bought one of those "green light" things and stuck it up under my right floorboard. It has done absolutely nothing. I have a light at the end of my street that is long enough to watch grass grow. I wait what I think is a reasonable period of time and if the light hasn't turned green I just go through the red. One of these days I'll get stopped by a cop and I'll just have to deal with it.
 

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Here in Tennessee, I couldn't care less about a red light. I don't even wait 2 seconds anymore if there is no one else approaching the intersection. I go. Why wait to see if the system detects or not? I get the being safe part, but I think I can tell when its ok to just go.
 

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Yup, just stop with your front wheel over the the cut in the pavement where the sensor coils are buried. The metal wheel should be enough to disrupt the electro-magnetic field which triggers the signal switch.

More info in this link.
http://www.msgroup.org/Tip.aspx?Num=148&Set=
 

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That's the ticket - live life on the Edge.
Not really on the "edge" unless you are just being plain stupid about it. In Missouri there is no "proceed with caution" clause for vehicles unable to trip a traffic light sensor. That means of course, all of us that do it are technicly breaking the law.

So, you don't do it in front of a cop....and you sure as shiit do not do it unless it is obviously safe to do so.

There is a traffic light near my house that seems to a bit iffy about detecting a bike. Good news is there's about a miles view ahead for oncoming traffic, so the only chance you'd be taking if there are no cars to be seen is getting a ticket from a cop hiding in the bushes.

So, no living on the edge here....when I said I would rather run the light...(as opposed to sticking a strong magnet under my bike) I did of course mean when it is safe to do so.

There have been a few times where I have had to move up and let the car behind me trigger the light....only because there was too much oncomming traffic to safely turn in front of them.


I seem to have less trouble now with my FJR then I did with the Vulcan BTW.

And the senosrs do not detect "mass" they detect metal. The magnets are supposed to help disrupt the sensors magnetic field by impossing their own. If you put 30 tons of silicon gel over the sensor it would not trip...but place an iron skillet on the outer line and it will.



KM
 

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My understanding is that the loop detects the surface area of conductive material in the same plane as the loop. ( "skin effect")
For example, a 6" square of sheet metal held level to the road would be the same as a 6" square block of metal. That same 6" square of sheet metal, held perpendicular to the loop, would be undetectable.
 

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In Ohio if the light does not recognize a motorcycle (a registered motor vehicle) the light is defective. The light must recognize all motor vehicles. In the event that the light is defective, you treat it like a four way stop. The reality, however, is that you are the only person there who knows the light is defective, so you make a legal stop, then proceed with caution when othere traffic is gone. If you are stopped, it is likely the cop will not know this law.
 

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This is where my old man would have said, "the graveyard is full of people who said that."
He may have applied that more to the idiots who say "Hey buddy, Watch This !" or "I think I can beat that one across".
I definately was not implying that I would test fate. I'm just sayin' if it is safe, I don't wait very long at all as apposed to waiting 5 minutes for something that may or may not happen. lol.
 

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The "loop" of wire in the road has a current running through it. The current running through the wire is creating a small magnetic field that surrounds it. When a ferrous material (contains iron) comes close to the field, it changes the resistance to current flow in the wire. This change in current is detected by the electronics of the signal light controller. The signal light electronics are "tuned" to detect a certain change in current within the wire to say a vehicle is "present". The amount of ferrous material that is within the cross-sectional plane of the magnetic field is important, the shape is not. Theoretically, a magnet would change the current as it was passing over the loop. but when the magnet stopped moving, there would be no more induction of current into the wire. Iron good. Magnet not good.

You know,... if you put a siren and flashing lights on your bike, you can get some of those stubborn lights to change too. :)
 

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The "loop" of wire in the road has a current running through it. The current running through the wire is creating a small magnetic field that surrounds it. When a ferrous material (contains iron) comes close to the field, it changes the resistance to current flow in the wire. This change in current is detected by the electronics of the signal light controller. The signal light electronics are "tuned" to detect a certain change in current within the wire to say a vehicle is "present". The amount of ferrous material that is within the cross-sectional plane of the magnetic field is important, the shape is not. Theoretically, a magnet would change the current as it was passing over the loop. but when the magnet stopped moving, there would be no more induction of current into the wire. Iron good. Magnet not good.

You know,... if you put a siren and flashing lights on your bike, you can get some of those stubborn lights to change too. :)
I do not believe your description is correct:
1: non-ferrous materials work as well, if not better; aluminum, for example.... it's all about conduction. The question is if the object has free electrons that can be induced to move (conductive, not necessarily ferrous) by the small magnetic field generated by the loop. If a sufficient current can be induced in the object it will create it's own magnetic field, proportional to the loop, and in opposition to it. (resisting it, for lack of a better term) This secondary field acts on the loop's field, thus reducing it's frequency. I do not believe it has any significant effect on the wire's resistance.

2: The magnet doesn't work because it's field is not a function of the loop's field..... the magnetic field of the object must 'modulate' in response to the loop. a permanent earth magnet will not do this. ( at least not enough to make a difference)

3: I think it is frequency, not current, that is being monitored by the electronics.

4: again, it's surface area normal to the magnetic field of the loop that matters. ( thus, parallel to the wire )

5: I could be completely wrong on the above :)
 

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Actually, It’s probably a mix of the two or both Dariv. I do think the ferrous part is important, because it is the iron that “assists” the flux of the magnetic field. That is why an iron core is the material of choice for transformers. But maybe it would be more correct to say that the object (car), affects the “inductance” of the circuit that the wire loop is part of, and therefore changes the current flow within the circuit. It could also be detected by a change in the resonant frequency of the circuit. In electronics, there are usually more ways than one to “skin the cat”. I’m sure there have been many approaches taken.

I however, will not dwell on it, I will merely stop appropriately, look both ways, and move on down the road. :beerchug:
 

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Actually KM we do have a fairly new law in MO about this. It went into effect in August of '09.
Joem, after reading the bill from the link you provided, I would be concerned about condition #2: "The traffic signal continues to show a red light for an unreasonable amount of time" (bold emphasis mine). It seems open to too much interpretation. What is unreasonable? My idea of unreasonable certainly won't be the same as the cop who pulls me over. It's unfortunate that they utilized such flimsy wording in writing this up. Unless it's more clearly defined, I'll still be watching for LEO's before crossing against any red. Just my two cents...

John
 

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I know. Nice of them to be so clear. I have done some other reading on it, mostly some articles in different papers and a few blogs. It was written more to make it an allowable argument to use as a defense in court. I think that even with the law, if you do it enough you may get spotted, and could still be ticketed. I did have to talk at least one person down from the "now we can just blast thru lights all we want" misconception.
 
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