Tripping traffic lights

[dang]

Any secret to tripping traffic lights? Occasionally I ride late in the evening when traffic is low and I seem unable to trip the traffic lights. I have seen products that you can put on the bottom of your bike that are supposed to help - anyone ever tried any? Thanks.

Cheers,

Dan

[lauramonster]

Yeah, on a Harley - not a sportbike.  It's a magnet that lets the mechanism "read" you presence.   Not sure if the weight of the bike helps/hurts.
Seems like the magnet would have to be stronger for a lighter bike. 
Is there an engineer in the house??

[ducatiz]

if you dig around on google you can find a guy who had the same problem and put some neodymium magnets under his bike..  i read it and moved on, i just run the light.

[skisteep]

the sensors are wires embedded in the pavement, one along the stop line, one about 10 ft behind the stop line one in the center and one up each side of the lane about 2 ft from the shoulder and the center line.  Your best bet is to stop over the wire.

[mxwinky]

Yes, they work.  I sold them for years when I was in the bike biz.  They stick to the bottom of the bike and trip the field when you ride up to the light, and they actually do a decent job.  A new unit came out just a year ago which was supposedly better, but I never got any complaints from any of my many customers who bought them.  Now if I could just remember the name . . . guess the memory is the first thing to go.

[marsrr]

A neo magnet is what you need put it on your oil filter. also benefits the oil filter as the magnet collects materials in the oil. neo magnets are small and power full

[somegirl]

There was a recent thread about this here. Some people suggested putting the sidestand down.

[ROBsS4R]

There was a recent thread about this here. Some people suggested putting the sidestand down.

Really... Hmmm

I will try it tonight on a left hander that will never turn for me.

I always have to go straight and make a U turn and then make a right 

[Goldeneye]

I haven't had any trouble with the S2R 1k.  I just position myself along the edge of the embedded wire.  In my area the wire is in a circle...

I've heard if you position in the middle of the circle, which is looking for changes in a magnetic field, bikes don't have enough metal to make the required change.

So, I position over the edge, and no trouble so far...

[Bigbore4]

Most of em, shutting the engine off and re-firing (with the electric starter!) will trip them.  The starter motor generates a pretty good magnetic field.

There is this one stubborn light at Bunker Lake Road and Crosstown that will not trip.  It wont even trip with a car behind you.  If it's a light you know about, pull well off to the side of the lane and wave a cage up beside ya.  Works every time, assuming a convenient cager!

We finally got a law passed in MN, if you are on a bike and miss one cycle, you can proceed.  I hear the law is somewhat subjectively interpreted.

Or, like the man said, run it!

[ROBsS4R]

No luck for me

I tried putting my kickstand down and leaning the bike. I also restarted my bike but I could not trigger the light

[ellingly]

No luck for me

I tried putting my kickstand down and leaning the bike. I also restarted my bike but I could not trigger the light

You need to play with positioning a bit more. The way the wires are arranged there are dead spots. Where the dead spots are is a bit hard to say, because it depends on the geometry of the loops.

You also have to realise that a narrow, and bits of metal high up away from the road, are harder to trigger the system(1). Cars have floor pans which, in general, are lowish to the ground (raised monstertrucks notwithstanding, but they're just massive conductive things). Ultimately, it's the conductance (conductivity multipled by the volume) that matters and the separation (signal falls off with the square of distance) that matters.

The sidestand trick works if you can find a sweet spot. The bottom of the sidestand is close to the ground, well, should be very close unless your bike likes to fall over. The starter trick works because

The magnetic thing... I'm not sure. It's not something I know anyone to have actually worked - they triggered the lights without as well, when they were removed... the times it didn't work have been due to . Needs further testing. The signal induced in the receiver loop due to even a rare earth magnetic should be fairly small, in fact. It also depends on the system - lots will filter out signals which look very funny. Starters induce spikes which start to look like the frequencies used (sort of), so they sometimes aren't filtered out. It can also be more of a problem to get them to trip in areas with lots of electromagnetic noise, or lights which are supposed to trip to let people turn into other roads - they need to be set up to be very sensitive so they don't detect cars driving in the lane next to them.

How do I know this shit? Well, I have friends who work on these. I'm a geophysicist, and we use electromagnetic systems to find things.

(1) A frequency domain electromagnetic system (FEM). Transmitter coil transmits a time-varying signal (usually a sine wave), sets up a magnetic field, which sets up an electrical field in any conductors, which then sets up a secondary magnetic field which is detected as a time varying signal at the receiver coil. The amplitude and phase difference of the transmitted and received waveform is a fairly nasty but resolveable function of conductance. Frequency-domain electromagnetic systems are also used as metal detectors, for simply interpreting their response in terms of conductive materials is easier than the other option (time-domain electromagnetics - TEM).

[Duc L'Smart]

Look very carefully in all directions, run the light [moto]

[johnster]

Look very carefully in all directions, run the light [moto]

+1.... No cop, no stop!! 

[somegirl]

Look very carefully in all directions, run the light [moto]

Some intersections are too busy for that.