Spark plugs again....

[thebeast]

What spark plugs should be used with aftermarket panheads? The manufacturer is unknown, so i'm guessing VTwin Mfg, Milwaukee Twin??? I use J12Y on my OEM heads but these look like there's more thread depth maybe requiring a longer reach plug?
Thanks, James

[foundationapps]

I've got STD heads, they use long reach plugs.

Autolite 65 is my plug of choice. Common at parts stores. Running manual circuit breaker.

[48Doc]

HD 3-4

[thebeast]

Thanks for your response. But is it necessary to use long reach in these heads? If so, what are the Champion numbers? Are the ones you fellas recommended long reach? Seems to me the difference between a j12y and a comparable plug, with the same amount of exposed electrode, but with the electrode threaded deeper in the head would make a big difference in heat. Maybe someone could explain this to me.
Thanks, James

[RUBONE]

James,
A champion plug identical in heat range to the J12Y in 3/4" reach is an N12Y. Very basic plug available anywhere. It may also be listed as N12YC. The depth of the threads has no bearing on heat rating, they are designed for the same range regardless of thread length. You are way overthinking this.

[thebeast]

Thanks Rubone. Bad habit!
James