wideAMG

try this a night in your car.
when approaching a red light with no one in front of you rapidly flick you high beams on and off. this simulates the flashing lights of emergency vehicles and immediately changes the red to green.
this will be dependant on angle and frequency but i was effective with hand held strobes sold to cyclists.
new technology may have changed this but it did work at one time.

challaday

Most lights in the city I work for are based on transponders in the emergency vehicles. People can illegally obtain one of these transponders and switch lights as they cruise through town. Big fine if you are caught with one.

We are starting the process of replacing induction loops with cameras that feed a computer system with pattern recognition capabilities. They can "see" cars in the turn lanes, pedestrians at the sides waiting to cross, etc. They work great with bikes and pedestrians because they use infrared to sense body heat.

Slicks

you're smoking crack.

most emergency vehicles get through using infrared light, that's what the little sensor on top of nearly every pole mast arm is. others do, as mentioned, use transponders...but that's becoming dated.

also, there the two most commonly used detection systems today are wireless/camera (looking for any lasting disturbance in a field), and induction loops (mentioned above by others). the way to trigger these induction loops is doing exactly what others have said - pretty much lay down your bike so that your hubs match up with one of the sides of the loops in the road.

source: i'm a traffic engineer...

CrimsonKarter21

If the loop doesn't recognize you and your bike, lean it close to the ground. If it still doesn't pick up the bike, treat the light as a malufunctioning light and roll it. You won't get a ticket. There was something about this on cyclingnews I think about road rules.

waterrockets 

Ever feel like you're talking to a wall around here?

This is the answer folks.

/thread

Hamish200sx

In response to the OP's statement about not having a button to push. If there is no way for a pedestrian to signal a light then it is on a timer and you just need to wait your turn. If you are already doing this and the light is going through a full rotation without letting you go then call it in to the city.

urbanknight

I don't think that holds true in CA. I'll have to look it up to be sure, though.

msincredible

Not necessarily, it could be sensor-triggered for cars but without any crosswalks for pedestrians (they have to go over a block or something).

I agree that the OP can report it as a malfunctioning light.

HopHornbeam

Don't know for sure if this works or if it's more of a coincidence, but when I ride at night and come up to a red with no traffic going the other way (on the green), the light will usually turn if I shine my headlight on the traffic lights.

Velo Vol 

Zombie thread

79pmooney

In Portland, OR the sensors are typically ~3 foot diameter circle under the pavement roughly under the engine of a car stopped at the light. I find I can often trigger the light by sitting about 5-6 feet back of the stop line and around 3 feet into the lane. I watch in my mirror for left turning cars. If I guess the driver to be assertive, I move to the lane edge and allow him to pull up to the sensor. If I guess the isn't, I stay out there. Missing sequences because I didn't trigger the light pisses me off. (All the town/city/county has to do to make it easy for bikes is paint the bicycle emblem on over the sensor, That they choose not to strikes me as discrimination against a class of road users that has been around longer than the aurtomobiles they pamper with my tax money. When my presence means that the car also misses the sequence? Welcome to my world!

CargoDane

Oh, effing great. Hadn't noticed just how old this thread was.

msu2001la

They usually look something like this. As others have said, even on a fancy carbon bike the metal in your spokes, pedals and drivetrain should be enough to trigger it. Often cyclists are rolling past or around the loops without realizing it, and then stopping too far out in the intersection to trigger it. Riding in the middle of the lane as you approach, and stopping on top of the loop should be enough to trigger it.

CargoDane

Carbon fibre conducts electricity (lightning too!). Even a full CF bike, with ceramic bearings an whatnot cn be heated with induction. Pure plastic: No. Carbon fibres in plastic: Yes.
So, yeah, the coil will trigger if it triggers for other bikes.

datlas 

It is close to Halloween, right?

rubiksoval

Run it. That's not even illegal if it's clear.

WhyFi

Not every state has dead red laws.

rubiksoval

Too bad for them. I'd still run it.

WhyFi

Oh yeah - I still run 'em, too, but it's not legal.

Davespix

Mount a small high power magnet to your frame or shoe and move across the sensor buried in the road. Some motorcyclists need to do this too.
Edit: after a bit of internet research this seems to have been a false solution. Best attempt is to park on one of the corners of the loop.

Racing Dan

Is there no button to press, and what about pedestrians? Magnetic shoes? :-)

Carbonfiberboy 

On a left turn signal, that's the only thing you can do, but it's safe enough if you watch for a cycle to see how the signal works. And if there's no pedestrian button, again that's what you have to do. I don't think you'd have a cop problem with that. If it's a light you have to use all the time, complain to your city or county traffic engineer's office. They're supposed to fix that, and sometimes they do. It's a huge hassle for them. They have to close the intersection and experiment with various bike placements. This is only a bike issue if they already have sensors in the road, so it's really just a matter of adjustment. Probably costs them $1000 to adjust one though.

The sensors will work with alu wheels - frame material doesn't matter. The engineers told me that they work best if one lays the wheels down flat where you see the sensor cable leaving the sensor pattern, though I've never had to do that. OTOH if you run carbon wheels and frame, you're maybe SOL. Same thing if they've paved over the sensor without painting a bike glyph in the right spot. Some towns around here have painted bike glyphs on every sensor. Not mine, though. There's a real SOB on one of my routes where one has to cross a busy highway at a light with no pedestrian button. There's another one where if one pushes the button, only the crosswalk goes green and the traffic light stays red. Total PITA for groups which send a rider over to push the button and haven't been there before.

Bmach

Those that say to push the ped crossing button, I hope you walk your bike across and not ride your bike.

wheelingmike

Has anyone try something like this? Do they work?

https://greenlighttriggers.com/

Davespix

some people claim that they work but technical experts show how they should have no effect. Seems someone tried to market a “veloloop” but there was not enough interest. Lots of information available searching for “traffic light trigger” on the internet.