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2021 CanAm Spyder RT
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Does a magnet stuck underneath a motorcycle make any difference in whether or not the cycle is picked up by the in-ground sensors that control the traffic light sequence? My Goldwing generally triggers the sensor, but my much smaller scooter does not. Maybe its just the mass of the vehicle, but I know that some claim that a strong magnet can make the difference. Thoughts?
 

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I don't know about magnets, but I get consistently good results by stabbing the front brake over the sensor area. I don't know if it's weight or what, but it triggers the light every time.
 

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The magnet may trigger some signals, but not all. I have heard of some that would sew the magnet somehow onto their boot to get the magnet closer, they're claiming it makes an improvement. But I don't know.
 

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I thought the sensor was triggered by mass / weight. A cage triggers it, a bike does not. Other variance could be the 2 wheels side by side, crossing at the same time. But I do not think so. Grabbing the front brake at the right time, puts more down force on the sensor, which would be the same as more mass.

UK
 

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I think this came up on a topic about traffic lights not working for motorcycles. Now I've slept since then but it seems it wasn't magnetism or vehicle mass, but a sensor in or under the pavement that detected electrical activity from a vehicle's engine area.

So you might need to park right in the middle of the lane where the road is the nastiest, greasy, slickest mess to trigger the sensor.

(I added that last part so don't take it as gospel.) :)
 

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Zip
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Sometimes I've had success putting down my side stand and leaning the bike over. My theory is that it puts enough iron right into the middle of the coil.

Sent from my LM-V405 using Tapatalk
 

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Wow. A sensory circulating system. Maybe the cone heads had it right. We need to do some tests.
In NZ there are rubber strips across the road activated by pressure. They are set at a distance so you know, if you have gone over the pad when the light goes orange, you can proceed. Outside the pad, you are required to stop. This removes the guess work.

I used maximum brakes in the rain on Sunday, when the light turned orange. Good test of the new brake pads on the XS400.
Pads made in Italy. Boycotting England, except for triumph parts. The fairing was also made in Italy.

UK
 

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I use magnets designed to hold stuff while it is clipped to your belt. I bought two and clip them to the bottom of my fairing with some gorrilla tape to secure it. Seems to work. :devil: :angel:
 

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Pretty sure the below pavement sensors around here use old fashioned metal detector technology, which is a coil and a tuned circuit that detects via a capacitance shift when metal is proximate. A magnet will help in that it's just a little more metal, but I don't think the detection system is using magnetism or requires ferrous metal.

By situating my machine over the left or ride side of the approx 4x4 patch in the pavement, I can put it's metal closer to the coil, which is a big horizontal loop and then have a better chance of being detected. This seems to work, but I haven't done any kind of scientific test. Mostly, if I'm the first to arrive at one of the intersections where I know one of these sensors lives, I pull far to the right and encourage the next car to move to the front. There's never a much of a shortage of "next cars" here in Chicago.

Chicago also has a fairly recent law on the books that allows bicycles and motorcycles to proceed through a red light after 120 seconds of waiting, if the light shows no sign of changing, and the way is clear. It's like the red light becomes a stop sign, legally speaking. The law specifically references the fact that motorcycles may be unable to activate the sensors.

I guess there's at least one benefit to living in the big city.
 

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That's a good "explainer" video. Most of the signals in our city are now using the video detection and no longer the inductive loops. The temperature changes between winter and summer frequently resulted in the loops breaking and losing their conductivity. The video detection works much better for bikes and MCs.
 

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Chicago also has a fairly recent law on the books that allows bicycles and motorcycles to proceed through a red light after 120 seconds of waiting, if the light shows no sign of changing, and the way is clear. It's like the red light becomes a stop sign, legally speaking. The law specifically references the fact that motorcycles may be unable to activate the sensors.
Georgia has a similar law. But to keep within the Georgia way of doing things, they had to complicate it a little. The time period required to wait at the light is defined as "a reasonable amount of time" . So if the riders definition of a reasonable amount of time differs from an officers definition of a reasonable amount of time, we have to go see the judge to see what his definition of a reasonable amount of time is. :surprise:
 

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I've taken the option a few times, but only when there was absolutely nobody around and I had been waiting long enough to become conscious of the wait and think, "Damn, is this thing EVER going to change!?"

That "reasonable man" legal definition is just there to keep lawyers fat and busy spending our money.

My buddy says he wants to go through right in front of a long line of cars waiting patiently during rush hour, but that seems like rubbing their noses in it. The cagers are already jealous of us, ... why rub it in?
 

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Reasonable amount of time when there is absolutely no one in sight is just a few seconds for me. Yet if Mr./Mrs./Mss Officer is parked at the curb happens to be watching, then my full stop, look and proceed is likely to get me a ticket. That's my few seconds and reasonable amount of time. I treat stop lights like stop signs when no one is approaching from the sides. Yep, it will get me a ticket some day but I feel down right stupid just sitting there when there is no reason to except for a dumb traffic light. Reasonable to me, simply can't be defined in seconds or minutes. But that isn't what that officer goes by. When does common sense enter into this? I refuse to let some light tell me what I can and cannot do. But I'm prepared for that ticket too. I won't cry about but I certainly will bitch about it because it is stupid.

So use good judgement with your reasonable amount of time is all I can suggest.
 

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The loops are what we have around here for the most part, and I can vouch for not requiring ferrous metal, just plenty of any metal such as aluminum. I doubt a magnet would make a difference.

The smaller bikes I've ridden, even with tubular steel frames, like the VStar 650 or Kingpin, just don't seem to have enough mass to get them to respond, but my 900 pound Vision, which is almost entirely made of cast aluminum except for hardware and some steel engine parts like gears and crankshaft will always set the off, it's the amount of any metal that's required.


Pretty sure the below pavement sensors around here use old fashioned metal detector technology, which is a coil and a tuned circuit that detects via a capacitance shift when metal is proximate. A magnet will help in that it's just a little more metal, but I don't think the detection system is using magnetism or requires ferrous metal.

By situating my machine over the left or ride side of the approx 4x4 patch in the pavement, I can put it's metal closer to the coil, which is a big horizontal loop and then have a better chance of being detected. This seems to work, but I haven't done any kind of scientific test. Mostly, if I'm the first to arrive at one of the intersections where I know one of these sensors lives, I pull far to the right and encourage the next car to move to the front. There's never a much of a shortage of "next cars" here in Chicago.

Chicago also has a fairly recent law on the books that allows bicycles and motorcycles to proceed through a red light after 120 seconds of waiting, if the light shows no sign of changing, and the way is clear. It's like the red light becomes a stop sign, legally speaking. The law specifically references the fact that motorcycles may be unable to activate the sensors.

I guess there's at least one benefit to living in the big city.
 

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Zip
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Ohio has a law but it is written specifically for bicycles and electric bicycles. The fact that vehicle classes are enumerated and motorcycles aren't in the list tells me that I'd better make darn sure there's no cop around when I run the dead red light.

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Many years ago, about 0130 in downtown Honolulu, I was waiting for a red light to change on my 68 350 Kawasaki. I waited forever. No other vehicles. Finally I went thru the red, and promptly got pulled over by the local fuzz. We chatted, I was polite having had a couple of beers, he was getting the ticket ready. What set him back, and settled the issue was, I asked him how I could legally get out of my predicament. There were two lanes in each direction, I was in the one closest to the middle of the road.

You can not change lanes at an intersection, you can not make a U turn, you can not go thru a red light.
It must have been a favourite spot for him during the late night hours. Used to be the flat foots would sleep. This guy was in an unmarked car. Cops there used to use cars of their choice.

UK
 
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