Ric in Sac
Well-known member
A technique that works for me is that while waiting at a traffic light I reach back with my left foot and ground the center stand. It doesn't work 100% of the time but it does make a positive difference. 
Green Light Triggers
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Geezer
Parsimonious Curmudgeon
IMHO, a cop is a police officer. LEO is more generic and covers police, sheriff and deputies, state troopers, DEC officers (environmental conversation), DEP officers (environmental protection), basically anyone authorized to give out traffic tickets. In fact there are no actual police officers in my town.
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First of all there is RADAR based sensing, Photo based, and Inductive reactance based sensing. Photo and RADAR needs no explaination.... Inductive reactance takes some 'splaining. Read on if you want to know how. Go back if you don't want your head to hurt! :lol:
Technical explaination....(Inductive reactance)
Any current flowing through a wire will create a magnetic feild around it.......
A DC current will create a feild that never collapses. An AC current will expand and collaps at the rate of frequency. Creating an continually expanding and collapsing "electro magnetic" feild.
The wires in the street that form that loop is an inductor. A wire of any given length forms an inductor with a given fixed value if inductance. Other inductors include the coil on your speakers, the windings of a tranformer, even an antenna is an inductor. Now lets look at the wire in the road...... It is an inductor and as such has a given "inductive reactance". Inductive reactance is the effect that an inductor resists the change in current flow. (current lags voltage in phase) Inductors are the opposite of capacitors. Capacitors have "capacitive reactance". Capacitors resist the change in voltage. (voltage lags current in phase) Now put these two together in parallel and you form a tank circuit that is tuned to a given frequency. Stimulated with a ac frequency at the tuned frequency and the tank will oscillate. And it's output can be measured.
Now lets jump back the the inductor. The inductive reactance of a given coil (wire) is influenced by the "core". That being the material it is wound around. Inductors can be "air core" (like those hollow coils found in radios). Or iron core tranformers (like the tranformer you find in every piece of equipment). Or a speakers coil wrapped around a fixed magnetic core. (the magnetic feild created by the current flow in the speakers coil will react to the fixed flux field produced by the magnetc core and make the speaker move) Any piece of wire is influence by the material it is wound around air having the least affect and an iron slug the most affect.
Now lets look at the wire in the street with relation to the tank circuit, the core material, and the frequency of the tank. The tuned frequency will vary with various cores. Think of any vehicle as being the core. Cars being very large with lots of STEEL (iron). Now think of your bikes. I have an '82 CBX. STEEL frame. No problems with the stoplights. But my FJR is plastic and aluminum. Neither of which has much affect on the inductive reactance of the coil wire. Try to find the STEEL parts on the FJR. (NOT MANY). And the reason many modern motorcycles have problems with stoplights.
As to the gadgets that claim to trip the lights.... The magnetic fields produced be these (or you starter for that case) do NOT change the inductive reactane of the wire. They may influence a current into the wire but it does NOT change the inductive reactance of that wire. Only the iron content of your vehicle does. Don't waste your money of them. Positioning yourself over the wire helps. Dropping you centerstand down over the wire may also help. But it is the sensitivity of the circuitry that really determins if the sensor wire will actually sense you are there based on you vehicles influence on the inductive reactance of the tank curcuits coil wire. Some moden stoplights are pretty sensitive to moderm vehicles. But older system are not. They will still easily detect automobiles but moderm motorcycles are difficult to detect with older (less sensitive/less adjustable) systems. Some municipalities attempt to adjust the sensors to sense motorcycles. Others don't care.
In my state I can run a red if I give it a chance to sense I am there. If not I can procede with caution but only after I have given it a chance. (meaning at least one cycle)
I have actually put my side stand down and walked over to the "walk" button and pushed it in some cases! I hate it when they don't sense me!
Sorry for the LONG explanation. But now you know how the wire in the road work. You can say you "lernt" something today!
John
Technical explaination....(Inductive reactance)
Any current flowing through a wire will create a magnetic feild around it.......
A DC current will create a feild that never collapses. An AC current will expand and collaps at the rate of frequency. Creating an continually expanding and collapsing "electro magnetic" feild.
The wires in the street that form that loop is an inductor. A wire of any given length forms an inductor with a given fixed value if inductance. Other inductors include the coil on your speakers, the windings of a tranformer, even an antenna is an inductor. Now lets look at the wire in the road...... It is an inductor and as such has a given "inductive reactance". Inductive reactance is the effect that an inductor resists the change in current flow. (current lags voltage in phase) Inductors are the opposite of capacitors. Capacitors have "capacitive reactance". Capacitors resist the change in voltage. (voltage lags current in phase) Now put these two together in parallel and you form a tank circuit that is tuned to a given frequency. Stimulated with a ac frequency at the tuned frequency and the tank will oscillate. And it's output can be measured.
Now lets jump back the the inductor. The inductive reactance of a given coil (wire) is influenced by the "core". That being the material it is wound around. Inductors can be "air core" (like those hollow coils found in radios). Or iron core tranformers (like the tranformer you find in every piece of equipment). Or a speakers coil wrapped around a fixed magnetic core. (the magnetic feild created by the current flow in the speakers coil will react to the fixed flux field produced by the magnetc core and make the speaker move) Any piece of wire is influence by the material it is wound around air having the least affect and an iron slug the most affect.
Now lets look at the wire in the street with relation to the tank circuit, the core material, and the frequency of the tank. The tuned frequency will vary with various cores. Think of any vehicle as being the core. Cars being very large with lots of STEEL (iron). Now think of your bikes. I have an '82 CBX. STEEL frame. No problems with the stoplights. But my FJR is plastic and aluminum. Neither of which has much affect on the inductive reactance of the coil wire. Try to find the STEEL parts on the FJR. (NOT MANY). And the reason many modern motorcycles have problems with stoplights.
As to the gadgets that claim to trip the lights.... The magnetic fields produced be these (or you starter for that case) do NOT change the inductive reactane of the wire. They may influence a current into the wire but it does NOT change the inductive reactance of that wire. Only the iron content of your vehicle does. Don't waste your money of them. Positioning yourself over the wire helps. Dropping you centerstand down over the wire may also help. But it is the sensitivity of the circuitry that really determins if the sensor wire will actually sense you are there based on you vehicles influence on the inductive reactance of the tank curcuits coil wire. Some moden stoplights are pretty sensitive to moderm vehicles. But older system are not. They will still easily detect automobiles but moderm motorcycles are difficult to detect with older (less sensitive/less adjustable) systems. Some municipalities attempt to adjust the sensors to sense motorcycles. Others don't care.
In my state I can run a red if I give it a chance to sense I am there. If not I can procede with caution but only after I have given it a chance. (meaning at least one cycle)
I have actually put my side stand down and walked over to the "walk" button and pushed it in some cases! I hate it when they don't sense me!
Sorry for the LONG explanation. But now you know how the wire in the road work. You can say you "lernt" something today!
John
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SilveradoSlick
Well-known member
But John, if I trip some lights by hanging a rare earth magnet under my bike, I don't consider it a waste of my money. I'd be happier if it tripped every light I encountered, but I'll take what I can get.
madmike2
Shtirrenuppenmeister
I always try to ride on the "edge" of the loop, i.e., to towards the center of one of the traffic wheel tracks. Then, at the signals I know don't read my bike, I kick the centerstand up and down a couple of times with my left foot. This has worked so far.
John, you're right--you made my head hurt. :bigeyes:
+1 for riding over the wire loop/sensor imbedded in the road. I can trigger a gate at work with my old 10-speed bicycle (has plenty of steel in frame) if I get it positioned exactly right.
Why doesn't somebody who believes in the Magnet Thingie, take it off the bike, go to a wired stop light, dangle it a few inches above the area of the wire loop/sensor, and see if you can get it to trigger. Then you would know if it works, and how close you will need to be to the wire loop.
As John said, older systems sensitivity may vary, but would be interesting to see if it works at all.
+1 for riding over the wire loop/sensor imbedded in the road. I can trigger a gate at work with my old 10-speed bicycle (has plenty of steel in frame) if I get it positioned exactly right.
Why doesn't somebody who believes in the Magnet Thingie, take it off the bike, go to a wired stop light, dangle it a few inches above the area of the wire loop/sensor, and see if you can get it to trigger. Then you would know if it works, and how close you will need to be to the wire loop.
As John said, older systems sensitivity may vary, but would be interesting to see if it works at all.
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SilveradoSlick
Well-known member
Yambone,
My experimets have been with certain lights on my regular commute which were never triggered by the bike without the GreenLightTrigger but were consistantly triggered with it attached. Enough evidence for me. Unfortunately there are some lights (fortunately not on my regular commute) which are not triggered by the GreenLightTrigger.
My experimets have been with certain lights on my regular commute which were never triggered by the bike without the GreenLightTrigger but were consistantly triggered with it attached. Enough evidence for me. Unfortunately there are some lights (fortunately not on my regular commute) which are not triggered by the GreenLightTrigger.
