I've just tested my Ignition coil, following the advice in Rupert Ratio Vol 2 pg 287
It says there that for 6 V system one should get a reading of circa 1.7 to 1.9 Ohms or for a 12 V system a reading of circa 3.3 to 3.8 Ohms between the two LT Poles
I have a 6V B40F Star.
I'm getting different readings depending on where I press the probes on the LT poles.
On each pole there is a spare connecting tab. I'm guessing the nuts on the connected terminals will add resistance. Jamming the probe into the hole in each of the spare copper tabs seems to give the lowest reading which was 2.9 Ohms. However cleaning the tabs reduced the reading to 2.5 Ohms.
(There is no continuity between LT & HT poles ... as should be the case)
I already know the bike will run with the coil, BUT should I be concerned that the different Ohm readings to that Rupert suggests may affect engine running/performance ?
I wouldn't be too concerned if your contacts are clean. The results show there is continuity and the figures are not a million miles off.
I am sure there is some variation between coils and also can you be sure that your meter is very accurate. Unless it has been calibrated against a set value, then I would be doubtful your meter is that accurate.