I have not measured the actual current draw but the stock coils have bugger all resistance ( 0.34 ohm) so I would say its fairly high , but then the dwell time ( the time the current actually flows because the coils are switched on and off so the current flow is not continual ) must be reasonably short. You could put an amp meter in series with the coil but I doubt that it would tell you anything useful as the coil powers on and off 100 times per second at 6000rpm and the meter wont display that fast . You could hook a coil up to a battery with the amp meter in series and that would tell you the continual current flow but again not all that useful. To get a accurate idea of whats really going on would require an oscilloscope and the nouse to figure out what its telling you...... any how ,if your thinking about fitting new coils , Dyna do a suitable replacement but you would have to do a search here as others have done this but I cant remember what coils they used.
Hamish
I wish I was young again............Id be heaps smarter than last time
Yeah, I was also afraid that you would need an oscilloscope for it.
I was curious which wire diameter I could take the best.
A specialist told me to keep 5A per square millimeter (17awg) as a maximum for motorcycle wire loom.
I have 3ohm Dynatek coils but have no idea what they actually draw during the 360 degrees cycles.
Just curious ...
For fuse purposes you need to look at the continuous current being drawn at switch on when the engine isn't running. A 3Ω coil will draw approx 4 amps, so 2 coils will pull 8A. When the engine is running, as stated above, the current draw will be much less.
About a decade ago I installed green 3ohm dynacoils, had a bracket fabricated and used Magnecor ignition leads - the bike ran significantly better thereafter.