Introduction: Rare Earth Magnet Magnetic Induction Loop Trickster for Cyclists.

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 ?

Comments

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rafununu made it!(author)2015-03-16

With neodym magnets, you must take care not to overheat them, they will definitely lose their properties.

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BikeWrenchMorgan made it!(author)2015-03-18

That's true enough. but the heat gun doesn't produce enough heat to harm them. that's why I use that instead of a torch.

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krisyow made it!(author)2015-03-17

Would a dynamo hub, or a bottom bracket dynamo accomplish this as well?

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BikeWrenchMorgan made it!(author)2015-03-18

I'm not sure if it would. I do know this works as I've been using one for a couple of years now.

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SimonAshmore made it!(author)2015-03-18

BB? I assume Bottom Bracket, but since you don't say, or include any pictures of this stage, it's anyone's guess.

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BikeWrenchMorgan made it!(author)2015-03-18

Yes it gets taped to the bottom bracket.

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bscholtz made it!(author)2015-03-15

I dunno if im missing something , but what exactly is the tiny magnet suppose to do? my MB is completely aluminium.

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BikeWrenchMorgan made it!(author)2015-03-16

I posted a link to a video in the comments. the magnet tricks to inductive coil in the pavement into thinking there's a car on it thus causing the traffic light to start it's change signal.

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tylerkat made it!(author)2015-03-15

I'm actually wondering how such a small magnet can achieve what you say it will. It seems that the magnet itself would have to be closer than the lowest point on your bicycle or am I missing something?

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BikeWrenchMorgan made it!(author)2015-03-15

here's a video link https://youtu.be/8GAacxGiV4A

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BikeWrenchMorgan made it!(author)2015-03-15

tylercat, I've been using mine for a couple of years now and they actually do work. I have one on my mountain bike which has a fairly high BB. it doesn't take much of a magnetic signal to trick the induction loop. just enough for it to think it's picking up on the steel frame of a car or light truck. there are several YouTube videos out there showing these little magnets in action.

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fred3655 made it!(author)2015-03-15

Any old magnet works, the stronger the better. I wrapped the lowest part of the frame with electrical tape and used a couple of zip ties to attach a bar magnet.

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BikeWrenchMorgan made it!(author)2015-03-15

That's very true. Any magnet will work. However, these ones are discreet and are tucked out of the way, giving you the most bang for your buck. For anyone concerned about additional weight, this weighs in at under 3 grams. Most commuters probably aren't so concerned by weight, but some are. Also aesthetics come into consideration for those who may want to have it tucked out of sight. You do have a valid point though about any old magnet working. The reason I went with rare earth magnets in the first place is their strength vs size and weight.

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