Cerberusgl

At my work we keep a chunk of metal next to the automatic gate so when we need to get out after hours we wave the metal over the sensor area. Although sometimes it opens just by riding over it, the sensor that is. In CA for motorcycles there is a law the bike can proceed with caution if the light does not change.
§ 21800. Intersections without functioning traffic control signals or yield
sign, or with all-direction stop signs, except left-turning vehicle with
vehicle
approaching from opposite direction

(a) The driver of a vehicle approaching an intersection shall yield the
right- of-way to any vehicle which has entered the intersection from a
different
highway.
(b) (1) When two vehicles enter an intersection from different highways at
the same time, the driver of the vehicle on the left shall yield the
right-of-way to
the vehicle on his or her immediate right, except that the driver of any
vehicle on a terminating highway shall yield the right-of-way to any
vehicle on
the intersecting continuing highway.

(2) For the purposes of this section, "terminating highway" means a highway
which intersects, but does not continue beyond the intersection, with another
highway which does continue beyond the intersection.

(c) When two vehicles enter an intersection from different highways at the
same time and the intersection is controlled from all directions by stop
signs, the
driver of the vehicle on the left shall yield the right-of-way to the
vehicle on his or her immediate right.

(d) (1) The driver of any vehicle approaching an intersection which has
official traffic control signals that are inoperative shall stop at the
intersection, and
may proceed with caution when it is safe to do so.

(2) When two vehicles enter an intersection from different highways at the
same time, and the official traffic control signals for the intersection are
inoperative, the driver of the vehicle on the left shall yield the
right-of-way to the vehicle on his or her immediate right, except that the
driver of any vehicle
on a terminating highway shall yield the right-of-way to any vehicle on the
intersecting continuing highway.

(e) This section does not apply to any of the following:
(1) Any intersection controlled by an official traffic control signal or
yield right-of-way sign.
(2) Any intersection controlled by stop signs from less than all directions.
(3) When vehicles are approaching each other from opposite directions and
the driver of one of the vehicles intends to make, or is making, a left turn.

See section D 1

Rowan

Carbon frame and bars and wheels and pedals, stainless chain, alloy chainrings and Ti sprockets, pedal spindles... not much ferro maagnetic stuff there. But wait, there's still steel there in the ball bearings

khuon

I guess it's the steel plate of my Speedplay cleats that's allowing me to trip the sensors. Actually, my carbon frame does have a bit of steel in it. There's a steel insert (along with aluminum in the middle section) in the headtube and seattube of my bike. Also, remember that not all stainless steel is austenitic.

Txthroop 

Here's an letter written by someone who seems to know what he's talking about. I've been following his advice with good success. (WHen you get to this site click on "site index" under the main title and then scroll down to "Traffic signals, triggering them.") https://bicycleaustin.info/ A little further down in the discussion there is a guy who reports on a trial he did with the Green Light Triggers.

Daily Commute

I complained to our city's bikeway coordinator, and he gave me a personal lesson on how to trigger lights. He said that if I can't make them work, he'll talk to the powers that be to see if he can increase the sensitivity. I tried his technique this morning on a light I have never been able to trigger, and it worked.

In the attached diagram, I have marked the most sensitive portions of the sensors. Place you bike directly over that portion of the sensor. On rectangular sensors, that means your bike will be on the crack. Even if my diagrams are not perfect.

khuon

Yep... I believe that was what I was trying to say in a previous post.

jukt

Some lights have a light sensitve trigger. Only ones near schools, hospitals, firehouses, etc.

In Maryland, school bussses and other vehicles have a strobe light to trigger them.

Not sure how it would work for a bike.

Daily Commute

But the key is not just to be on the wire, but to be on the right place on the wire:

khuon

This is only half-right. The goal here is to intersect the magnetic field and cut as many magnetic gradients as possible. Unless physics has changed since I last took E&M, the lines of the magnetic field will flow perpendicular to the loop direction as per the right-hand-rule. Thus the field will be toroidal in nature. The highest concentration of the gradient will be directly over the wire. Okay so actually the highest concentration is in the middle with the loop actually surrounding you like in an MRI scanner but since it's buried in the ground, you'll have to settle for the next best thing. Thus to provide the best chance for a return flux, you need to be positioned as much directly over the wire as possible. In the case of the diamond shaped loop, this may mean actually positioning the bike at an angle. Also, moving the bike about can help increase detection too by setting up additional flux ala the motor effect.

Daily Commute

khoun, would you say this diagram is more accurate?

khuon

Yeah. I believe so. The quadrapole loops are the most complex and interesting case since you have two distinct magnetic induction fields interacting (aside from those fields generated by the target). This is actually why they're so effective. The nice thing about them is that they're quite effective even between the wires but the greatest chance of detection is still by being positioned along the middle wire as you've shown in your diagram.

Felt Z65

I'm the original poster and I appreciate the good information starting when folks really started addressing my question. Thanks a lot people; I'm looking forward to trying these positions out.

ruralite

The red light triggers do really work, though there are some sold at auctions that are too weak. I have one called RLC-40 from redlightchanger.com that's the most powerful made, but there are others you can search for using google or alta vista search engines. The key is to get one with a lifetime warranty that's coated with epoxy, and use it correctly by tracking your motorcycle right over the sensor wire marks on the pavement. I never get stuck waiting for red lights again, unless the traffic light is broken. Then all you can do is notify the local traffic department. Tennesse allows you to run the red light, but you better be ready to prove to the cop that the light is not working!

Raiyn

Like the ones you sell for $20. Sorry but your competition has you beat by $5 and has a better website

telenick

The Institute of Traffic Engineers bears the greatest culpability since 1982 when it was sued over the death of a cyclist who was forced to run a red light.

Run the light ...just be careful.

80sMutRider

In most places they will have what is called a "Clear Box" (a little clearish cilinder next to traffic lights), what the purpose of this "box" is, is to set up a "trigger-based algorithm", they can be programmed for different numbers of lanes, set up to which lanes turn, go straight, and do both. It is quite effective, and costs less than the sensors that are dug into the ground. Also what these are good for is that they can be programmed in with the set pattern of emergency vehicles (most cities with these have all lights, firetruck, ambulance, and police all running on the same timers) when the "clear box" picks up one of these patterns it automatically/quickly turns green, allowing the traffic to be safer for the emergency vehicle and for the cross-traffic.

In most cities it is ILLEGAL to copy the patterns with strobe lights to turn the light for you, and the little metal magnet isn't going to do the job.

I'd scope all of the intersections that you usually ride and see if they have the rectangles in the ground or the "clear box". If you have the rectangles, go the the city/town hall and ask if it is legal to attach one of these to your bike, better to be safe than sorry.

ruralite

"Like the ones you sell for $20. Sotty but your competition has you beat by $5 and has a better website"

I appreciate your feedback, and I'm sure the other changers have something that's good, and I won't knock other products, it's just that you usually get what you pay for. I've tried them all, and the one I have on my bike has nearly 10 times difference in strength, epoxy coated, patented material, lifetime warranty, vs. 30 day warranty, etc, etc, etc. and it's a good value. The RLC-40 RedLightChanger is more expensive to make, and you're right: the website isn't as fancy, but it's still the best product. And the company who makes it, whom I won't mention, will stand behind the product 100%, as all companies should. But I'm not selling the product here, and although it works on bikes, it's not made for bicycles, it's too heavy, at about 1.5 ounces, it's for motorcycles, and this is not a selling forum.
Robert

Jackpiner

This website sells a traffic Light trigger, I bought one, was sceptical at first, but it seems to work... $10.95 - https://www.cyclecolor.com/id47.htm
Make sure you mount it at the lowest point on your motorcycle.