This is a simple and easy to make (also inexpensive) device which fools magnetic induction loops into thinking there's a car on top of them. This makes an traffic light so equipped go into its change sequence.
Step 1: Buy the Magnets. I Purchased Mine From Amazing Magnets at Www.amazingmagnets.com and Will Purchase From Them Again.
These are neodymium rare earth magnets, and as you can see they're quite small. 3/4" × 1/4" × 1/16" and the total weight of the finished product is just under 3 grams. So no weight adding issues for those who have such concerns.
Step 2: Buy Some Automotive Shrink Tubing.
Select the right diameter shrink tubing and cut it to length. As a note to avoid frustration, these magnets are very strong and will attach themselves to the scissors from an inch or more away! So measure and cut using a tape measure.
Step 3: Insert the Magnet Into the Tubing With a Wooden Implement.
Push the magnet in centering it as best you can. It's not a crucial step per sé, but is fairly important to help keep the magnet inside from being exposed to the elements as they will rust.
Step 4: Shrink the Tubing
Carefully use the heat gun to effectively shrink the tubing around the magnet. It won't create a prefect seal, but it will be effective enough to keep the elements out. I also added a drop of silicone on each end to improve the seal, but this isn't a necessary step. Use caution when working with a heat gun as they do get very hot and can give you a nasty second or even third degree burn.
Step 5: Place Outdoor Carpet Tape on the Assembly
This is the second last step. The unit is now complete and is ready to be taped onto the BB of your daily commuter to help with light changing in urban areas. Look for the diamond or square shaped cuts in the pavement as these indicate where the induction coils are placed. Center your bikes over top of the cut lines as this will have the greatest effect. Ultimate placement is to have the magnet in line with the BB so it shows itself to the induction coils at 90° for maximum results.
Step 6: Ride Your Bike!
I apologize for using someone else's photo here, but new phone and no real pics of us or my previous projects yet. Please ride safe and obey all traffic laws in your area. There's someone out there who's thinking of you, so ride safe and meet up with them like the couple in the picture. Enjoy and I hope this has helped you out ?