Is there a simple way to test the Ignition Coil?

[RickTaff]

I think my coil may be on the way out as my bike struggles to start even when warm, and cuts out after engine is warmed up; also seems to misfire when riding. Resulting in a stutter, hesitation.

Have changed Spark Plug, cleaned carb. But have been advised my symptoms are also those of a failing coil, so is there a simple way to test the coil?

Wont have a Multi meter until middle of week, as mine is broke so need to borrow one, have been told of some test which involves removing the spark plug cap from the plug, inserting a screwdriver into spark plug cap and holding near engine block to see if there is some sort of spark while hitting the electric start... seems a bit dangerous to me.

Any advice massively appreciated, cheers.

[Rogerborg]

Leave the plug in the cap, and hold the plug against the engine using gloves or insulated pliers. Darken the area if possible, then crank. You should see a strong blue spark across the plug gap.
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[Kickstart]

Hi

That is the normal way to do a quick test. Although you can just stuff a plug in it and hold the plug against the engine while you do it.

But that won't tell you how healthy it is. The manual will have a range of values for resistance of the coil, and it might work while outside those ranges. Hence you really need a multi meter. Even then things change with temperature.

Also some coils have an integrated cdi unit. In which case full tests might not be possible with a meter.

All the best

Katy
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[RickTaff]

[RickTaff]

[WD Forte]

saying what bike /type of coil would help
Coils can look Ok resistance wise, then breakdown as they heat under load
A rough and ready test is to measure the primary LT
and secondary HT windings ( on common simple coils)
Primaries are usually very low, about 1 ohm or less
and secondaries very high, say 6 Kilo ohms or above

12V DC coils will test a bit differently to AC CDI coils
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[WD Forte]

Reading the symptoms again it could be other things than the coil or plug.
Saying what bike would really help you know.
It could be AC source coils, CDI box, fuel starvation due to faulty vacuum fuel tap, faulty fuel pump, intermittent supply to ignition, bad grounding, bad connectors and so on..............

but as we don't know which if any of these you may have, its guess work or tarot cards
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[Robby]

Seeing as this can be whichever bike I want it to be, the problem is with the ignition windings on the stator. Unplugging the multi plug under the tank with 3 yellow wires going in will help the bike start and run, but will mean the rest of it isn't charging.

In the spirit of the thread, I'm not going to tell you which bike is fixed by doing this.

[RickTaff]

[WD Forte]

Mechanic eh? that's a broad term
problem is compression and valves?
hmmmmm.........
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