Coil test

[EricWoods]

Anyone got a solid test for my coils. Got orange and white wires going into both coils and Ht lead coming outta each. Any way I can stick my meter across them and test?

Eric Woods
Dub

[Dave8338]

If you have the book, though I've not had to do it, it should tell you what the ohms of resistance should be. Other than that, not sure. Someone here will have a better answer for you. :?

[Jaguarjoe]

You can always do a "file test":
Get a coarse file and gound it. Hook up a wire to the points side of the coil and drag the other end of it across the file. Sparks should fly at the spark plug.
Ohm meter checks don't always work because all you need is one shorted turn in a coil and it won't work anymore. An ohm meter won't detect one shorted turn out of the many hundreds of turns in the coil.

[rockford]

Coils

Coils are really simple. I suspect many coils have been replaced when the real problem was discovered a week or two or three later.

[hikermikem]

What bike do you have? Does it have points or electronic ignition? The coils are different between the two types of ignition.

[Greg O.]

You can always do a "file test":

Thats a new one to me. Good idea, thanks,

Greg O.

[slamonte]

Coils can be tested with a digital volt / ohm meter. The ohm meter mainly test continuity of the winding (open / short). Basic readings can be read by putting the negitive lead on, then the positive. The primary side should read between 1.5 to 3.0 ohms depending on the coils and your bike specs. The high voltage side (secondary) can be tested by putting the one meter lead on the negitive terminat and the positive lead on the output post or sparkplug cap. the resistance should be between 7000 and 25,000 ohms. This is dependent on your bike and components installed. Use your service manual for the specific numbers. If you have aftermarket stuff you'll need to lookup their specs.

You can also take out a sparkplug, check for the proper gab, then put the sparkplug cap back on and ground the sparkplug tip to the engine (away from cylendar open hole). crank the engine a few times and what the spark. if the spark is strong a blue, it is putting out a good spark.

Be careful in doing the spark ground to case. If the wire or sparkplug cap is cracked or freyed, you could get jolted. Wear a heavy rubber dish washing glove for safety. The auto parts store sell a little device you clamp to the head, set the game on this device, take you sparkplug cap of your norm saprkplug and hook it to this simple device. It will show the same spark jump. This eliminates the sparkplug in your trouble shoot. It is also fast since you do not need to remove the spak plugs. Just move the wires over to this device one at a time to check each lead. It ran $7 US

[Billy Ricks]

If you have stock coils and electronic ignition you should get 3-5 ohms on the primary side of the coils. The primary side is where your orange/white and the ignitor wires plug in. The secondary side should measure 30k-50k ohms with one probe in each plug cap coming from 1 & 4 then 2 & 3.