Trigger GREEN Traffic Lights




Tinkerer, hackster and prankster. Hit me up on Facebook:
if you or someone you know, owns a motorcycle, a scooter or even a small car, you've probably noticed that it's easy to get stuck at traffic lights. Well, I'm going to explain why it happens and show you a great little trick that will save time, gas and frustration by getting you a green light every time.

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Step 1: The Problem...

At most traffic lights and turn signals, you will notice a loop of wire buried in the pavement of the road near the stop line. This is called an Inductive-loop traffic detector that operates by sensing a change in frequency to the electromagnetic field over the coil of wire. In other words, when a car pulls up, it senses the vehicle and the light changes. Most motorcycles, scooters, bicycles and small cars don't have enough conductive material to trigger these loops and change the traffic light.

Step 2: The Solution...

Produce a very powerful field that increases the inductance in these traffic sensors, and causes the light to change! Here's how to do it...

Step 3: What You Need!

2 Neodymium magnets. I chose two from CMS Magnetics that have a pulling force of over 6lbs each. I also bought a roll of heavy duty exterior mounting tape.

Step 4: Attach It...

After cutting off a small strip of tape, I attached it the magnets. Then I applied it to the bottom of our test scooter, perpendicular to the road.

Step 5: Optional Step & Video

Because magnets rust, I put them stacked together inside a waterproof, rust-proof, pill holder or Bison Tube and then stuck this to the bottom of the scooter. Should last a long, long time! Now here is the video!

You can learn more about how this works Here

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    412 Discussions


    Reply 1 year ago

    Why would I (or anyone on here) like your page? Your just doing publicity for your own products. I for one still won't trust these types of devices until I see hard evidence. And I wouldn't pay the 50$ you're asking either. While they may not be 100% reliable, most green lights trigger most of the time anyway. If not, just get a bigger bike.

    Lisa Ander

    1 year ago on Step 5

    It still works, all lights are green ahead of me.


    2 years ago

    There is another solution which really works.

    I developed the active electronic device coupled with loop
    antenna. The device receives the signal, measures it, and transmits a specially
    generated signal back to the induction loop. As a result, the sensor thinks
    that a large vehicle is passing above.

    It works with all induction loop sensors conforming NEMA
    standards, in the frequency range of 10 to 200 kHz.

    I sell the devices on eBay:

    1 reply

    Reply 2 years ago

    The loop pictured is called a Quadrapole loop. It is most detectable over the very center wire. Pull your bike over the center wire it should detect you.

    Thanks, Charles


    3 years ago

    If you are at a red light and no one else is there waiting at the intersection and lets say you wait there like this for about 5 minutes. Do you run the red? If it was red for 15 minutes would you really sit there for that long with no one around? what about 1/2hr or 1hr?


    3 years ago

    This is nonsense. Induction loop systems are triggered by eddy currents created by a resistive change in magnetic flux.
    For starters, the magnetic field created by the alternating current within the coil has no effect on the polarity of a permanent magnet. Meaning that magnet will have no more effect on the magnetic field produced by the primary coil than any other piece of equally conductive material of the same size, which when compared to the size of your bike, is practically nonexistent.
    In reality, when a large piece of conductive material passes over the field, the induced current creates a new field that disrupts the current of the initial loop.
    It's that *change* that triggers the computer into knowing you exist. In the same way, a car parked over a sensor does nothing. Entering and exiting the perimiter of the loop triggers the sensor.

    A tiny magnet will not have any effect, and any small effect would not be due to it's own magnetism.
    Try laying the bike down toward the sensor.

    1 reply

    Reply 3 years ago

    There's no question that a permanent magnet will create a *different* induced current in the induction loop than that produced by induced eddy currents in the conductive material of a large vehicle, but it certainly isn't nonsense. As your scooter, bolstered by permanent magnets, drives over the induction coil, the coil *will* see a changing magnetic flux which induces a current. When your scooter stops, the induced current will also stop. That should make your scooter look pretty much like any other vehicle that enters the loop and then comes to a stop (unless the tripper is designed to look for the continued presence of a stopped vehicle through the use of alternating current - I don't know if any are programmed that way). I suspect this idea would work for pretty much any traffic light, because they can't be programmed to be terribly sensitive to any particular signature - different vehicles will all create slightly different induced current signatures.


    4 years ago on Introduction

    I don't think we have these here in Michigan except in a few places. I thought they were timed throughout the day as to rush hour traffic,etc. I thought the traffic cams people take care of traffic control. duh is me. I never even heard of this metal detection things in the roads. News to me!

    Ludwig Von Mech

    8 years ago on Step 5

    In Wisconsin this is no longer a problem, as in 2010 we got a new law that allows bikes to wait and proceed through the red if traffic allows. I used to report all the lights that did not work, but now I don't bother. I just ride through.

    7 replies

    Does the rule apply to my SMART car or scooters? If so, maybe we'll move to WI.
    Sometimes we just get kind'a P.O'd and run the dang thing. Anytime the authorities stop you - whether you're handcuffed and put in the back of the police car or not, it's considered an "arrest." So I feel the light has arrested me without cause. Never tested this in a court, but that's my story and I'm stickin' to it. ;)


    Just to Bicycles, scooters, motorcycles, and other similar traffic. A solution is to wait at least 1 minute, and then go if you are clear. Problem with "45 second" laws is that if the roadway is really busy, it does not matter; you still cannot get across a flowing river of steel.

    I've been treating signals with unresponsive road sensors as four-way stops for decades, even without the benefit of such a law. If I hadn't, I'd have died of thirst and starvation while waiting for the light to change ages ago!

    We have that here, too. But sadly, it doesn't apply much for heavy traffic when you have a line of cars behind you getting madder with each missed cycle and no opening to go. This is a helpful fix.

    Ludwig Von MechNatureGeek24

    Reply 8 years ago on Step 5

    You have a very good point.

    Another way to fix this situation is to become proactive; the inductive coils in the road will not trigger if they are out of adjustment. I have reported these for years and years, and I have also seen them become so bad that a pickup truck will not work. The state supervisor is on my email list, and he will send out a crew if someone complains. They do not have time or manpower to continually inspect each light.
    I will try this magnetic solution at a place that I know does not work.

    Also, if you are on a bicycle or moped, do not hug the curb. You will get old waiting for the change. Ride over the lines slowly, and position yourself directly on top of the transverse wire. If it is still working, you will trip it.

    Happy riding.


    5 years ago on Introduction

    This trick from Kipkay on YouTube DOES NOT WORK. I proved it by securing a powerful rare-earth magnet from a disk drive to the end of a 8-foot piece of PVC pipe and waving it over the inductive detection loop at an intersection with infrequent traffic. Nothing happened. The only thing that triggers the light to change is a large, ferrous object, like an automobile.