How can I test my coils?

In a recent thread I explored the best remedy to fix an ignition switch into which I had snapped off the ignition key while kickstarting my 1970 roadster (which has the switch mounted in the side cover).

I have not fixed that yet, but have been able to still use the switch; the broken key is in the lock barrel, which will still turn, and I can use the other part of the broken key to turn it, with a bit of fiddling; so could start and ride the bike with no problem. I also figured out that I could stop the bike by just stalling it instead of turning off the ignition (no kill switch on this model); which may have lead to a problem.

After a recent ride I stopped the bike by stalling it; but forgot to turn off the ignition. I then compounded the issue by plugging in the battery to a smart charger. I didn't realise that the ignition was still on for a week; and I am concerned that I might have cooked the dual RGM coil that I installed a year or so ago. How can I test the coil to see if it still works? I have a volt meter and lots of ignorance.

Disconnect one lead of the primary (battery) side of the coil. Set your VOM to read resistance (ohms) in the single to 10 ohm range. Your coil should read about 3 to 6 ohms (just a guess). If it has failed it will likely show infinite ohms.

And if you have electronic ignition they turn themselves off after a few seconds if they get no signal from the engine, this is to protect the box and also covers the coils.

I might be ok then; have Boyer.

If the battery is now fully charged why not try to start the bike?

Auto Electricion down the bottom of Arckers Road , Wairau valley has a big nasty coil testing machine, as would gordon mickeys in Taka , if theyre still there , and many others .
If you really want to see what your coils capeable of.

Boyer switches off, coil will not have been affected.