magnets on bike frame to change the traffic lights.

[DavidV-SoGA]

I've got some pretty strong magnets approximately 1 " L x 3/4" W x 1/8" thick... there're called "30 lb" magnets... they do have some more pull... two stuck together seems to take more than 30 lbs pull to separate them and if they snap back...make sure your fingers are not between them... more like snapping magnets !

Okay - figured I'd put 2 or 3 of these under my frame to help change the traffic lights with the buried magnetic strips in the pavement?

Is there anything on my bike that the magnetic field these things transmit that may disrupt anything on my bike from an electrical or magnetic point of view ?

Just asking... Thanks.

[Morgan Buchanan]

They don't really work. Take them out, walk over ot the sensor and put them RIGHT ON the coil. Nothing will happen.

You're correct in that 2 30 pound magnets together feel like more than 30 pounds. They EACH pull 30, so they hold together at 60.

I put 3 60 pounders together and tried the experiment...no dice.

A lot of cities are very polite when you call them and tell them they need to up the sensitivity of an intersection. They WANT them to work for motorcycles. In TX we passed a law saying they MUST recognize motorcycles and even bicycles. I've called several cities to tell them about traffic lights that didn't and in each case they lights were fixed in no more than a few days, once in just a couple hours.

[crew]

Mechagodzilla will find you irresistible.

but ...

opinions vary ...

all blessings ...

crew

[Morgan Buchanan]

Yeah, I did forget to mention you get humped by giant robot dinosaur aliens. Jeeze crew, you're such a surprise spoiler.

[Knight]

i bought some rare earth magnets for my children on the weekend

They got them stuck inside my 150lb magnet , i guess i chipped one while prying them apart
and overnight the R E magnet collapsed on itself into 4 pieces

[ISKIVT]

Originally Posted by crew

Mechagodzilla will find you irresistible.

but ...

opinions vary ...

all blessings ...

crew

A post like this will make folks believe you been playin' with Peyote, but what else is new?

[Chicago-Spike]

To make the light change, just stop the bike on a corner of the box you see cut out in the pavement for the wire loop. This always works here in Illinois

[Morgan Buchanan]

The loops are electromagnetically sensitive. Different places set them with differing degrees of sensitivity. That's why this magnet theory should work, but doesn't seem to do so.... See, your bike in over 700 pounds. Adding a 100 pound of magnet is like an 800 pound bike. So if a loop sensor won't notice an 800 pound bike, your bike, plus a 100 pound magnet won't do it. Additionally, that 100 pound magnet isn't 100 pounds AT THE LOOP, it's 100 pounds at the point of attachment. So if you drag a 2,000 pound magnet across the sensor, it'll probably notice. But the little 6 pounders "they" sell for the stated purpose? You're far better off taking Spikes suggestion and putting metal in the corner of the sensor so more sensor has more chance of "seeing" more metal and tripping. But the reality is that some sensors are simply set far too high to notice. They might not even notice one of those Toyota Yaris or Smart Cars.

[Rezin]

Originally Posted by Morgan Buchanan

They don't really work. Take them out, walk over ot the sensor and put them RIGHT ON the coil. Nothing will happen.

They absolutley DO work. I have used them for years. They trip the 2 stubbon lights near my old house, and also actuated the gate at the apartment I used to live at.

They have nothing to do with the weight of the bike, it has to do with the size of the magnetic feild caused by the FERROUS metals in your bike. Aluminum and plastic and such do nothing. a magnet however does emit a field, and if you are moving along the edge of the loop sensor, it will see the disruption, and change the traffic signal.

Some loop sensors are so out of whack, a freigt train would have a hard time tripping them, but a magnet will help in most cases. Been uing them for 10+ years, and pretty much everone I know uses them too. They definatley make a difference. They don't change every light every time, but it's enough of a difference to use them.... Not like it is expensive or difficult to install or maintain.

[wayner]

I know nothing about these magnets, but I do have a question:

Do these magnets mounted up under your bike ever attract things up from the road like nails, etc?

[ANV1L]

Your "theory" of the magnets is incorrect, Morgan.
The magnets produce a magnetic field. Basically, you are making the small metal area undernieth your motorcyle "appear" larger to the sensors.
They work. I had them on my bike for years. (Cow magnets, available at your local farm type stores.)
Tim

[jackandangie]

Originally Posted by DavidV-SoGA

I've got some pretty strong magnets approximately 1 " L x 3/4" W x 1/8" thick... there're called "30 lb" magnets... they do have some more pull... two stuck together seems to take more than 30 lbs pull to separate them and if they snap back...make sure your fingers are not between them... more like snapping magnets !

Okay - figured I'd put 2 or 3 of these under my frame to help change the traffic lights with the buried magnetic strips in the pavement?

Is there anything on my bike that the magnetic field these things transmit that may disrupt anything on my bike from an electrical or magnetic point of view ?

Just asking... Thanks.

Most traffic signals don't work on the principle of magnetism, they work on the principle of inductance. If putting a magnet on makes them change faster then it's the mass of metal that make up the magnets, not the magnetism. You'd have better luck if you strapped a manhole cover to the bottom of your bike.

Jack

Jack

[Boy Racer]

Originally Posted by jackandangie

Most traffic signals don't work on the principle of magnetism, they work on the principle of inductance. If putting a magnet on makes them change faster then it's the mass of metal that make up the magnets, not the magnetism. You'd have better luck if you strapped a manhole cover to the bottom of your bike.

Jack

Jack

Yer dead right Jack. The loops are and inductor and it works on interrupting the inductance which is tuned to a specific length. This is altered when you drive anything metal over the top on them.

[Morgan Buchanan]

the weight thing was an over simplification. The more a bike weighs, generally, the more ferous metal is involved. That's certainly far too simplistic, and inaccurate of course. And as I said, the sensors have a range of sensitivity. So if your bike is JUST under the amount of ferous metal needed to trip a sensor and you put on a magnet that's just enough to put you past it, yeah, it'll work. ta-freaking-da. So would dragging a metal bar under your bike.

I don't care if you put a magnet under your bike and think it'll trip lights or cure baldness. Maybe you're lucky and live in an area that just happens to be just on that margin where they do work for you. But do a search of the internet and you'll find that IN GENERAL they don't do much good, and the ones that are sold for the purpose generally do very little good, because they're too small. But on my VTX, I got some SUPERIOR magnets and tried it on a large number of lights that didn't trip without them, and they didn't trip with the addition of 180 pounds of neo magents, which is WAY more magnetic field than is sold for the purpose.

What DOES work is to call the city and say, "Turn up the sensitivity of the lights at 1st street and 1st avenue, please."

[BigMac1800]

I have a light near my house that will take 30 seconds to change in the strait lane and changes instantly if I move half my car or all of my bike in the left turn lane. Go figure on that one all you arm-chair scientists out there

[crew]

Originally Posted by wayner

I know nothing about these magnets, but I do have a question:

Do these magnets mounted up under your bike ever attract things up from the road like nails, etc?

Nails and such can not defeat Megalon

* see Morgan Buchanan for details

but ...

opinions vary ...

all blessings ...

crew

[crazyman]

I bought one of those bike magnets. $20 pissed away. Most lights around here are on a computerized cycle. I haven't been stuck at a light since that magnet fell off sometime last year.

[Tapper]

Having once worked worked in a traffic department (long time back) and having maintained the loop detector electronics, I can tell you that cities now use one of two types of sensor - inductive, and video.

Inductive loops are the most common, because they're cheaper. They work by sensing the changing in inductance of the coil of wire cut into the pavement. This is essentially a measurement of the mass of ferrous or conductive metal passing near the loop. Magnets have no effect on this whatsoever. Even so, some people convince themselves they haven't been suckered into buying a worthless device, and trying to convince them otherwise is just impossible. But - adding the magnets inadvertantly appears to work, because they are always trying to maneuver the magnets over the coil, and ofcourse, this also moves the metallic mass of the bike over the coil as well.

If you want to maximize your chances of tripping the detector, think rims. The sensitivity of the coil drops off with the square of the distance to the mass placed near it. Rims get close, and are mainly the thing which trips the sensors. Put your rims on top of the coil, near the front corner if you can, and you'll stand the best chance of tripping the light.

[halfabubble]

Originally Posted by ANV1L

They work. I had them on my bike for years. (Cow magnets, available at your local farm type stores.)

ANV1L cruises down the country road, oblivious to the cows mooing in agony as his bike sucks them into the barbed wire fence.

[Jimysan]

Originally Posted by halfabubble

ANV1L cruises down the country road, oblivious to the cows mooing in agony as his bike sucks them into the barbed wire fence.

Mmmmmmmmmmm . . . steaks. . .

[hasbro56]

Originally Posted by halfabubble

ANV1L cruises down the country road, oblivious to the cows mooing in agony as his bike sucks them into the barbed wire fence.

Now that's funny enough to turn my whole rotten day around!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Thanks.

[VTXDick]

Don't know about you guys, but THEY never had this problem...

[Duck]

I talked to a guy that installs traffic lights and he said none of those magnets trip the light.

[xdanman]

Next time you pull up to one, put your bike in neutral and put your kickstand down on the crack where the sensor is.
That'll work.

[12RPilot]

Sometimes I will pull forward and wave the car behind me to pull up onto the loop.

One time I put a huge magnet from a paper recycling conveyer belt under my bike. This thing picks up small cars if one could fit on the conveyer. On my way to the nearest traffic light I was stopped over a manhole cover and couldn't move. Burned up the clutch trying to get away. Had to cut it loose and leave it there. An hour later I saw a Ford Fiesta sitting over that manhole with a bunch of people gathered around. Poor fella couldn't move either. The wrecker couldn't tow the car off there because that would leave an open hole. They had to wait until the city could bring a replacement manhole cover. I read in the paper the next day that there was a reward by the police department for information leading to the arrest of the person responsible for the magnet. I heard through the grapevine that I was a suspect since the magnet was traced to the recycling center were I worked. So I went to a payphone and called in a tip that terrorists use huge magnets to get manhole covers off so they can plant dirty bombs under the city. This upset the local police so much that many government spooks were called in to verify the entire sewer system was free of dirty bombs. Naturally, this took the attention away from me. However, the latest revision of the Homeland Security Bill calls for registering magnets over a certain power. The recycling Center can no longer just throw away it's old magnets. They must be broken into small pieces in the company of a federal Homeland Security agent. True story. Spread it around.

[12RPilot]

O

[crew]

What the %@<k did you think ride bells are for



Stop at a light ...

Put your toe down ...

The ride bell tinkles reminding you to say a prayer ...

Your guardian angel chases away the road demons ...

The light changes ...

Wait until your guardian angel chases away the road gremlins ...

but ...

opinions vary ...

all blessings ...

crew

[Alan Hawk]

I can see where the confusion over magnets comes from. In quite a lot of cities the detectors are called "Magnetic Mass Detectors". What that means is that they detect ferrous metal, or metal a magnet will stick to. So people see magnet and they think it detects magnetic fields rather than detecting the mass of metal capable of being attracted to a magnetic field.

In Boise, a VTX 1300R simply does not have enough ferrous metal on it to trip most of the lights in town. In fact, Idaho has a law that says if you are on a motorcycle and sit through one complete light change for everyone else and your light did not trip, then you are legally allowed to run a red light.

It's still VERY annoying, and I've discovered that quite a lot of drive through resturants use magnetic mass detectors also, and my VTX won't trip them. However, many bicycles will.

For the person who mentioned running your rims over the dector several times to make it trip, aren't the rims on a VTX 1300R aluminum? Either way, this doesn't work. First of all the detectors close to the surface of the road are in the approach to the light, not where you stop. The dectors where you stop are burried further, below the pavement, so there is no scar on the pavement indicating where they cut into it to place or adjust the sensors. Instead, they paint 4 yellow 3x3 inch squars in a rectangular pattern over where they think the sensor is, and you are supposed to place your bike in that rectangle. The drivers manual for the state of Idaho says that if you are on a motorcycle you are supposed to stop at the thick white stop line, and then ease your bike forward until the white line is in the middle between the front and rear tires, putting your front tire in the cross walk. Doing either or both of these still doesn't work. I usually have to wait until another car comes up behind me, tripping the sensors as it approaches.

When I took the STAR motocycle safety course they said to just pull over and let a car pull up to the light and trip it for you, but....pull over where? I'm in the left turn lane, the VTX is big, there are cars to the right, and traffic to the left.

Anyway, I need a way to ensure that these things trip, especially the drive through ones. Since magnets don't work, is there any standard mod that does? I've added a chrome backrest and rear carrier to the bike, and at some point I plan on adding engine guards, will this be enough?

[coltergeist]

I have found that if I pull into the sensor area and bring the RPMs up a little bit from idle - it'll trip the sensor. I knew about the electro-magnetic field of the vehicle being what trips the sensor. Bringing the engine RPMs up from idle can increase your bike's electro-magnetic field. I'm not talking about revving up and back to idle - that's bad for your plugs. I mean just give it a little throttle and hold it there for five to ten seconds.

[1800 spec 3]

Originally Posted by Boy Racer

Yer dead right Jack. The loops are and inductor and it works on interrupting the inductance which is tuned to a specific length. This is altered when you drive anything metal over the top on them.

You are correct sir. I have NEVER had a problem, but here is what I do. Drive DIRECTLY OVER the strip. IOW, place the mass of metal in the bike as close to the strips as possible. If possible, I do as Spike said and drive as far to the end. I never thought about it, but I guess that does make it the corner--- and stop the bike on top. NEVER had a problem.