Failed "Razor Blade Test"

[Gretnakid]

So I was trying to read into charging system problems and dig myself out of the "motorcycle not charging club" and came across the razor blade test and thought I'd give it a try. As I understand it you simply need to turn the key on and your coil should be magnetized (don't need to have the bike running).
So I gave this a go and I seem to have spotted my problem, I'm not getting any magnetism around my field coil. Now with that said my field coil does get the recommended 4 ohms of resistance.
Here is where I get confused. I hear that to test the system further you should hotwire a wire directly from the battery to one of the field coil wires (black or green). So I guess I need some clarification on the procedure to do that (and how to get some type of lead from the battery to the field coil wire).

 

[Edgee2004]

post a wiring diagram for this bike and i can help you.
i had the same problem with my DT400 and the light also cut out, on the DT the lighting and charging coil are on top of each other. so re-wrapping was easy. converted it from 6v to 12v with a re-wrap.
also i have never heard of the razor blade test.

 

[Gretnakid]

This is what I've been using.

 

[arfstrom]

Razor blade, feeler gauge test, its the same. For me, one day, I was working on the valves, I had turn on the ignition, and the Lug wrench I was using for the adjusting the crankshaft, was stuck to the bolt.

basically the premise, is to get power to the field coil. Once that is energized, the magnet will attract anything. preferable something small, and less likely to damage your bike like a razor or feeler gauge. If your battery is charged up, you should be able to take a shielded wire about 3 feet long, by 16g , tuck one end onto the positive pole (somehow so it doesn't come off)
Then locate the wire harness. From behind the Yamaha battery cover, the connections to the rectifier and voltage regulator (VR), you can disconnect it for now while testing. we want to send power away from the VR. (leave key on position) apply volts to green line. while doing that hold your razor, or feeler gauge near the stator housing. They should snap to it. There is one more connector, to the left of the battery airbox cover. try from there.
Also since your playing with these wires, get some solid stats on them. From the VR test with the multimeter, and determine continuity, and the OHM's, (between green wire, and the brown wire) Then do that at every block going to the stator assembly. This will let you know that the VR is dead if that works. Since your playing next to the white wires, get the stats off of them too. They are all part of the same system, since your here, might as well determine if there is any problem.
Look up in the manual for VR/Rectifer troubleshooting. (VR is just replace if bad)

 

[Lou Ranger]

Also, make sure you are using an old-school single razor blade, or piece of steel that can be attracted by a magnet. Some blades that are stainless steel might not stick.