Spark plug advise needed

hhh said:
Unless you increase the plug gap, then there may be an improvement.
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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
 
htown16 said:
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.
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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.
 
When I brought my 74 Commando new it had Champion plug caps as well plugs, from the factory, but that was over 48+ years ago when I brought it in 76 old new stock last of the black kicker Roadster in Brisbane at the time.

Ashley
 
Since we got shit E10 petrol over here I've started using NGK BPR6ES rather than BPR7ES.
Plugs now run a nice light brown colour and pea shooter ends are not so sooty.

I run a Pazon Altair with standard original Champion plug caps and non resistor plug leads.
 
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