coils

[buff]

i have been getting fouled plugs on my gs1000, could anyone tell me how to test my ignition coils, by the way i have a dyna electronic ignition fitted

[Steve]

Pull one of the plug leads off, roll the rubber back, grab the metal tip. Crank the engine. You will soon know if they work. :shock:

If you want to simply test them with a meter (how boring 8-[), use the OHMS function, check the resistance across the input terminals. Without knowing what year your bike is, or which Dyna kit you have on there, you should measure 3-5 ohms of resistance. Now check from one plug cap to the other. Stock coils should measure about 15k ohms, not sure about the Dynas, but they should be similar.

Although weak or bad coils can cause fouled plugs, there are other sources, too. If the plugs are the wrong heat range, or if the carbs are mis-adjusted, you will see fouled plugs. Start with new plugs of the correct heat range (NGK B8ES are the recommended plugs) and start your testing.


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[mark]

You don't say, but I'm assuming you have DC3-1 coils.

Primary resistance should be 3 ohms
Secondary resistance should 13.5 K - 15.5K
You can also check voltage between ground and coil with magnet pointing away from the modules. Shouldn't have much more than a 1 volt drop.

Having said that, your plugs could be fouled for many other reasons. They could be oil fouled from bad rings or valve seals, or carboned up from a plugged air filter, or incorrectly adjusted carbs as Steve said.

[Billy Ricks]

Stock coils should measure 30k-50k, aftermarket 15k-20k on the secondary side.