We've all gotten stuck at red lights with magnetic sensors that don't seem to "see" motorcycles and we sit there trying to decide whether to sit there forever or just blow the light, in which case, you-know-who will suddenly appear.  Green light triggers sold on the internet are only magnets in a plastic case, so my solution was to buy a couple of magnets at Ace Hardware (about $2.00) and JB Weld them to the underside of the frame along with a cable tie for insurance.  The magnets come in different sizes so I chose a pair about 1"X2".  I don't think I've been stuck at a light since and they've been there about 2 years now.  

Another trick...for those without a magnet attached to the bike or a green light trigger...

...your kill switch and starter button.

I won't guarantee 100% success, but if you are stuck at a light then simply shut off the bike and restart it.

The power surge to the starter (and it's magnets) will create a field pulse that will very often trigger the roadway sensors as well.

I don't think that he was referring to the weight of the bike as much as the mass of the bike.  Figuring that more mass would be more easily sensed...

The antenna in the road simply detects a change or interruption in the field.  Metal objects or electromagnetic fields do that, but unfortunately they set the threshold sensitivity for objects with larger mass in order to trigger a light change.

So...   being a electronics tech by training, and having worked at a factory that made radar components with big-ass magnets on them , I realized that just sticking a magnet on may not work.  

You need to test the field of the magnet.   Or.... how far the magnetic affects go out from the magnet.   Remember back to your school days and the paper and iron filings???   I figured that I needed a field that reached from the bottom of the bike to a few inches into the ground, so I guessed about a foot.

How to find the range of the field.... the easiest way to test it is to use a compass, and I suggest using a cheapie compass as the magnets may ruin it. (yep,  a compass.... one of those direction finding things used before GPS).  

WHAT I DID......  

- I found a bunch of magnets laying around the house.  Some strong and nice sized, some tiny and powerful, some long and skinny and only so-so in the strenght department.

- I laid the magnets out on a piece of wood on the concrete garage floor.
- I then took the small cheap compass my son had and from a distance, slowly moved it towards the magnets (one at a time).
- When the needle of the compass started to move I stopped and marked the distance.
-  What I found was the long skinny magnet had around an 18 inches range.  yea!!   The others were less.  The small powerful one was the worse.
- I attached that magnet on the bracket on the bottm of the bike, with doulbe sided tape and some heavy duty duct tape.

TEST DRIVE:
- PITA light number one, just down the street from my house.  Previously I had to wait for a car or a second bike.   NOW.... the light trigggered......  Hmmmm.... "once is luck, twice is coincident, third time is fact ",  .... so, on to the next light.
-  PITA light two,  preivously took three bikes or a car to trigger..... now,  my bike triggered it....  WOW!   On to the next PITA light.
-  PITA light number three,  a turn lane arrow down by the grocery store.   It took a few weeks to get to it without a car behind... but ... IT TRIGGERS NOW!!!!  

- PITA light number four,  at work.... didn't work.....  

Well three out of four isn't too bad.  

EDIT: Note, I still need to be over the wire in the roadway.

Now durn, why didn't some of the list oldtimers from years gone by try out this neat sounding trick?   Must a been because they are old foggies and were out of touch with all them newfangled magnetic type thangs.



Or it might be that posts put into the Cafe eventually disappear on you.   And some of our oldest (and best) old members put their pics and stuff on picture sites like Photobucket that autodump stuff by stored age (and some of our best oldest tricks are so old they aren't even around any more).

Ah, the things that Ricochet or Savage Greg could have taught you young puppies ....  things you will never know 'cause even if you could locate the post in the archives you could never make sense of it without the attached pictures which Photobucket Inc. trashed years ago to save some server space.

Now, stodgy old places like gunloads.com,  heck,  they NEVER throw away anything -- them's real gun nuts and they make conservative biker types seem right modernistic in their attitudes towards not throwing anything away.

See, gun nuts ARE good for something -- endless data retention if nothing else.

diamond jim wrote on 03/24/09 at 20:04:20:

Reminds me of putting my magnet on, first mod I did!  Got one of those 250# rated utility magnets from Harbor Freight (go by one on the way to work, yeehaw!) with the eyebolt in the middle.  Just used the threaded hole for the bolt to bolt it to the bracket on the bottom of the frame (I'm guessing for a center stand in a different life?).  Went good until I went to tighten it down and the magnet kept pulling the wrench, and my hand/arm/scorchables into close proximity of the still warm exhaust.  Lesson learned: don't get too excited to bolt on new goodies, think first!  BTW, it works on most of the lights, only came across one by work it won't trigger.

Kris - $31.28 + FREE shipping

http://www.amazon.com/MAGNEPULL-XP1000-3-Tapered-Magnet-Leader/dp/B00772WOA8/...

or this one mounted on/under the frame rails:

http://www.amazon.com/Applied-Magnets®-Strong-Neodymium-Magnet/dp/B0012AWV72/...

Oh, ok. I saw that pic and didn't realize what OF was demonstrating. I get it now. There's a magnet on the kickstand. Clever!