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I have a problem. Can't trip trafic light sensors...

alfa147x

alfa147x

Lifer
I have a problem. Can't trip trafic light sensors on my moped
Anyone have a solution?

Moped (I've worked on it quite a bit since then):
img5298tg.jpg

$200 😀
 
I think they sell devices for motorcycles to set those things off for you. I saw it in a mail-order catalog somewhere. I think cyclegear was the name.
 
i've heard putting the kickstand down can work. on motorcycles, this will often shutoff the engine if you're in gear. no idea about mopeds.
 
Has anyone heard of laws allowing you to run red lights if on 2 wheels?

TakeNoPrisoners said:
I think they sell devices for motorcycles to set those things off for you. I saw it in a mail-order catalog somewhere. I think cyclegear was the name.
Click to expand...

Thanks. I'll look into it
Fenixgoon said:
i've heard putting the kickstand down can work. on motorcycles, this will often shutoff the engine if you're in gear. no idea about mopeds.
Click to expand...

Nope doesn't kill the engine. Though it's not a regular kick stand. You have to pull the moped back on to it.
 
Traffic sensors are basically electromagnetic sensors.

Turning off the motorcycle and hitting the starter helps make a bigger disturbance in the field. Same with putting down the kickstand, since the metal is now closer to the sensor loop. I've also heard of people attaching neodynium magnet to their motorcycles.
 
I'm on a cutting cycle 😉
exdeath said:
Eat more twinkies.



I know, it's inductive...
Click to expand...

kami333 said:
Traffic sensors are basically electromagnetic sensors.

Turning off the motorcycle and hitting the starter helps make a bigger disturbance in the field. Same with putting down the kickstand, since the metal is now closer to the sensor loop. I've also heard of people attaching neodynium magnet to their motorcycles.
Click to expand...

Just heard about neodymium magnets. Would this have any adverse result with the moped?
 
Alright to fix the problem this is what you need.

Buy one LARGE magnet, tape it to the bottom of the bike (center cross member of the center stand).. profit!

I had teh problem early on, but that fixes it. You need a large magnet that can disturb the EM field. I've had one on my bike for years no problems. The only thing you go to to is come at a decent speed and stop on the sensor, it usually works on the first try
 
alfa147x said:
Has anyone heard of laws allowing you to run red lights if on 2 wheels?
Click to expand...

It was considered but withdrawn in GA this year. Maybe next year.
http://allaboutbikes.com/motorcyle-...es-could-say-goodbye-to-red-lights-in-georgia

Some states like MN have laws that allow a motorcycle to ride through a red light, provided that:
You come to a complete stop
Wait a "reasonable" amount of time (like more than 1 light cycle)
No one is immediately approaching on either the road you need to cross or the road you will enter
 
As others said - kickstand, turn the bike off and on (apparently the starter motor trips them) or take apart a hdd and use one of the magnets inside.
 
I've told the MP's on base here that I'm required to run reds all the time as I get off work at midnight and there's few cars around to trip the light for me. They're ok with it.
 
SpatiallyAware said:
I've seen someone push their bike across the crosswalk

Personally, I'll wait a reasonable amount of time and just run it.
Click to expand...

lol... Heard that's illegal (which is retarded).

The sensors work when there's a disturbance in the (magnetic) force caused by 2 tons of steel. Bike's are barely a quarter that, and not as spread out. I knew someone who was an avid cyclist, and did so in groups. They tried to pile their (assuming aluminum) bikes on the sensor with no luck.

Interesting solution with the magnet and starter.
 
Imp said:
The sensors work when there's a disturbance in the (magnetic) force caused by 2 tons of steel. Bike's are barely a quarter that, and not as spread out. I knew someone who was an avid cyclist, and did so in groups. They tried to pile their (assuming aluminum) bikes on the sensor with no luck.

Interesting solution with the magnet and starter.
Click to expand...

Not all sensors are the same, but many of them are based on current detection. Under the road is a coil of wires with alternating current passing through. When nothing is on the road, the coil of wires is similar to the primary side of a transformer with nothing connected to the secondary. The circuit is self inductive and doesn't draw much current. When you put a large amount of inductive material on top of the sensor, it creates another path for the magnetic field to go; your car is like the secondary side of a transformer. Soaking up the magnetic field reduces the amount of self inductance on the primary side, which makes the circuit draw more current, and current is what trips the sensor.

So basically the question is how to create a magnetic short circuit. Instead of using a material that conducts electric fields (copper), use a material that inducts magnetic field (iron). Aluminum bicycles won't work because aluminum is a terrible inductor. Iron is great, nickel is good, cobalt is ok. The construction makes a difference as well. High quality inductors found in power transformers are made of multiple layers of iron that are magnetically separate from each other because the stranded design works better than a solid design. Soft iron is a better inductor than hard iron.

Permanent magnets on the bike might work depending on whether the sensor is looking for RMS current or peak current. Permanent magnets have one direction, but the sensor's field is alternating. Mixing a permanent magnet with the alternating magnet would mean the circuits impedance would go way up then way down, large spike up, then no current, then large spike, then no current. The RMS current would be slightly higher due to the large fluctuations, but the peak current would be much much higher.
 
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Imp said:
lol... Heard that's illegal (which is retarded).

The sensors work when there's a disturbance in the (magnetic) force caused by 2 tons of steel. Bike's are barely a quarter that, and not as spread out. I knew someone who was an avid cyclist, and did so in groups. They tried to pile their (assuming aluminum) bikes on the sensor with no luck.

Interesting solution with the magnet and starter.
Click to expand...

It's legal in a few states, iirc. If the light won't trip, you treat it as a stop sign.
 
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