Spark plug advise needed

Unless you increase the plug gap, then there may be an improvement.
Smaller plug gaps require higher voltages to get a reliable spark. With wide gaps, the spark is not as fat. It is a reason to use magnetos with high compression engines. But modern electronics might be better. Many years ago, I read a lot about combustion in aircraft engines. If you have low voltage, a wide gap is more likely to give you a usable spark. But for reliability a small gap with high voltage is better.
 
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Plug heat range might depend a bit on how much oil you are burning. When riding a motorcycle, if the motor misses, it usually needs to be fixed.
 
Joe Hunt magneto's run lower gap,18thu gap on the spark plugs and not the 25thu standard, but getting the right heat range for the plugs is important for a good running motor, but each bike is different, mine runs better and longer life with Champion plugs, NGK at the same heat range not so good after a week or so, but others swear by NGKs, but now non resistor plugs are being fazed out as well there are a lot of fake plugs being sold.

Ashley
 
I ran NKG BPR8ES in all of my Commandos. I'd start with 8's and they are not fouling I'd stay with them. Seems like for NGK's only the resistor type are available now. If you choose them don't run resistor wires.
No, that was my point above: The non-resistor equivalent BP7ES is still available, albeit now under the model # 2412. I run those with 5K ohm resistance plug wires. 5K resistance good. 10K not so good - probably no biggie but I prefer to limit total resistance to 5K ohms.
 
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