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Coils
- Neotrion
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04 Nov 2005 16:47 #6541
by Neotrion
Coils was created by Neotrion
I just wanted to see if anyone had any instructions with some pictures on how to test my coils. I think I am testing everything right, but if someone could find this I would appreciate it. Plus some values on the test points would be nice. I do have a DVOM, but my manuel has no pictures, so I can't confirm I am doing the right thing. According to the book, I would be at the edge of scale of the high tension side. I would just like to make sure I am doing this right.
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- wiredgeorge
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05 Nov 2005 10:20 #6663
by wiredgeorge
wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
Replied by wiredgeorge on topic Coils
I use a multimeter with a 20VDC scale. You can also use 50VDC scale.
There are only three tests and I have no pictures...
You can test voltage to coils.
You can make two impedence checks.
Voltage: Bike is not running. Place POS lead from multimeter on lug on coil where power is connected. This should be a yellow/red wire. Place NEG lead on frame ground. Switch on key. You should read nominally 12.5 VDC. If it is substantially more or less voltage, you have a proble. Less voltage means generally that in the path to the point meausured, you have loss. More voltage and you had best check you charging system.
Impedence checks. Low - With power to bike off, put your multimeter in OHMS 1X scale. Put one lead on one lug on the coil and the other on the other lug. The resistance should read about 3.8 OHMs (points style coils). If you have an igniter style ignition from a later Kaw, the impedence should be a tad less... just under 2 OHMs I think. This will tell you if the primary resistance windings on your coil are shorted or not... If the readings you have vary a lot from what I described, the coil primary windings are shorted.
Secondary resistance check... (bike off) Put multimeter in OHMS 20K scale or 50K scale. Put your leads on the metal in the plug caps. If you have resistor components like resistor wires or caps, this can screw up the reading. If you stuff is non-resistor, you should have between 15k and 20k OHMs resistance. A manual for your bike (or the coils on your bike) will tell you the specific value but if it is between 15k - 20k the secondary windings on the coil are likely good. If it is a lot more or less, the coils are shorted. If the plug wires come off the coils, it is better to check the secondary resistance at the metal contacts on the coil.
There are only three tests and I have no pictures...
You can test voltage to coils.
You can make two impedence checks.
Voltage: Bike is not running. Place POS lead from multimeter on lug on coil where power is connected. This should be a yellow/red wire. Place NEG lead on frame ground. Switch on key. You should read nominally 12.5 VDC. If it is substantially more or less voltage, you have a proble. Less voltage means generally that in the path to the point meausured, you have loss. More voltage and you had best check you charging system.
Impedence checks. Low - With power to bike off, put your multimeter in OHMS 1X scale. Put one lead on one lug on the coil and the other on the other lug. The resistance should read about 3.8 OHMs (points style coils). If you have an igniter style ignition from a later Kaw, the impedence should be a tad less... just under 2 OHMs I think. This will tell you if the primary resistance windings on your coil are shorted or not... If the readings you have vary a lot from what I described, the coil primary windings are shorted.
Secondary resistance check... (bike off) Put multimeter in OHMS 20K scale or 50K scale. Put your leads on the metal in the plug caps. If you have resistor components like resistor wires or caps, this can screw up the reading. If you stuff is non-resistor, you should have between 15k and 20k OHMs resistance. A manual for your bike (or the coils on your bike) will tell you the specific value but if it is between 15k - 20k the secondary windings on the coil are likely good. If it is a lot more or less, the coils are shorted. If the plug wires come off the coils, it is better to check the secondary resistance at the metal contacts on the coil.
wiredgeorge Motorcycle Carburetors
Mico TX
www.wgcarbs.com
Too many bikes to list!
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