Spark plugs for STD heads

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King
Posts: 373
Joined: Fri Apr 02, 2004 5:05 pm

Spark plugs for STD heads

#1

Post by King » Mon Jan 17, 2005 2:13 pm

Description: I would appreciate any info on a “hotter" version of the 5R6A or RN12YC

Hi All,

I’m running STD heads on my 51FL so I use the standard Evo plugs which are Harley number 5R6A. I believe the Champion equivalent is RN12YC. My plugs are developing a strange baked on carbon deposit on the “cold” side of the insulator and the ground electrode. I don’t believe it is oil fouling as my oil consumption is normal, the bike does not blow any white smoke, and subjecting the plugs to Mr. Cotten’s heat lamp test does not eliminate or change the deposit.

A fellow AMCA Chapter member suggested that I try a “hotter” plug as an experiment to see if that cleared up the problem. So I went down to the HD Shop looking for the Evo equivalent of the old “Number 2” plug but the parts dude said that such a thing doesn’t exist.

I bet it does. So I would appreciate any info on a “hotter” version of the 5R6A or RN12YC.

Thanks

King



1950bobber

Re: Spark plugs for STD heads

#2

Post by 1950bobber » Mon Jan 17, 2005 5:04 pm

King,
I also have a Pan motor with STD heads...I run Champion plugs 101 RN13LYC with no problem. Don't know if this is an appropriate plug for your application but it does well in mine.
Jim in Seattle "1950 Bobber"

panhead
Site Admin
Posts: 2471
Joined: Wed Dec 12, 2001 9:17 pm
Bikes: 1954 FL
Location: Holland

Re: Spark plugs for STD heads

#3

Post by panhead » Mon Jan 17, 2005 5:56 pm

I use NGK BP5ES in my STD's.

kell
Posts: 369
Joined: Sat Jun 19, 2004 2:58 am

Re: Spark plugs for STD heads

#4

Post by kell » Wed Jan 19, 2005 4:25 am

I use N11YC (no resistor).

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