Resistor plugs and upgraded ignition coil query!

Greetings everybody, I ride an '82 Heritage Special. Two days ago I upgraded the stock ignition coil to a Mike's XS ultimate coil . New leads and fresh 5k Ohm resistor caps . Currently running NGK BP7ES plugs and the bike runs great. I have also trialed a pair of NGK BPR7EIX irridium plugs. Both run beautifully and have a faintly 'biscuit' coloured read after a good hard run. I was always led to believe that doubling up on resistance in the ignition circuit was a bad idea. Is it possible that the alleged 82 Kv output of the new coil effectively overcomes the added resistance provided by the iridium plugs? Both the standard plugs and the iridium plugs are 7 in the heat range. I'm running 98 RON fuel with no ethanol in it. Will using the iridium plugs be a problem? Any advice appreciated . Cheers, Matt

Matt, long ago I had carbon-core resistor plug wires, resistor caps, and resistor plugs on my points-fired XS1B, and it ran fine. Yes, that's the worst possible combination. I now run copper-core plug wires, non-resistor plug caps, and easier-to-find BPR7EIX resistor plugs, and on points. Plug gaps always at 0.025". Still runs fine.

If in doubt, try to restrict the "resistive" component to just one.

Otherwise, I see no issue with using Iridium BPR7EIX resistor plugs...

Thanks for the advice. I'm having a bit of difficulty trying to find non resistor caps locally. I can buy them on evilbay. For now I'll keep those iridium plugs. They never foul and she starts 1st or second kick cold! Sometimes it takes a few more kicks to get to the 'second' kick

Just an FYI, those would be: NGK LZFH 8710....

Yes, the non-resistor NGK plug caps are very nice. Any local bike shop should be able to order them for you, maybe even an auto parts place could too.

I picked up a similar coil with some MSD spark wire and 45° boots. Much easier to deal with resister plugs than having to re-build your boots. Maybe it's easy to change the resistor boots, but I don't care.