Spark plug

[Phil C]

I'm going to buy a new spark plug for my 1965 B40F. The one in there at the moment is a NGK  B6E S. My instruction manual says Champion N5, which I guess might have been superseded by now. What is best to get?    Phil

[corneg2]

I used to work at the Champion spark plug plant in the Wirral before it closed, so I am a bit biased. I used to always use Champion in my bike until I went electronic ignition. SRM advised me to use NGK stating they were better suited to electronic ignition. Personally, I don't think there is a big difference. Go with what you find works best for your engine.

[idie]

Do as I have done and try and find N5 plugs not the later N5C as they have no glazing so can saturate with fuel when starting.

[Phil C]

Is there a more readily-available equivalent?  Phil

[Beesy]

NGK 6ES is the readily available equivalent

[AdrianS]

+1 for NGK.

To be honest I've never noticed any difference between makes.

[Beesy]

Me neither really. NGK seem to be more prevalent.

I've used both without noticing a difference. I did have one of those infuriating moments with a Champion plug years ago, when a new out of the packet plug was duff, spent hours checking everything else before I switched it for another brand new one.

But it was a one off experience

[Phil C]

NGK 6ES is the readily available equivalent

So I guess I he same as I have in at the moment:  NGK B6ES (I think the B just denotes the thread size.).     Thanks all.
Phil

[chaz]

https://www.ngk.com/ngk-spark-plug-numbering-systems

the B is the thread and hex size

personally, no other reason, Brit bikes get Champion, Foreign get NGK. Customers and my own.