Sparkplugs question

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Sparkplugs question


Post by suicideshovel65 » Fri Jan 16, 2004 11:46 am

Description: What are your recommendations re sparkplugs?

Hi everyone,

About time I asked a few more stupid questions:

1) What are your recommendations re sparkplugs?


2) Using the Champion website as a "control", for FL Pans (? - the actual website entry isn't clear on this) I believe I see J12YC as the model number, with a 3/8" reach and 0.025 gap.
For later FL shovels I see RN12YC with a 3/4" reach and 0.040 gap.
Can I use the longer reach plug if I adjust it to the same gap as the Pan plug and check first for clearance?
I ask this because I ride with a lot of shovels, and should I run out of spares (and vice versa)...



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Re: Sparkplugs question


Post by Cotten » Fri Jan 16, 2004 1:38 pm

Using a plug that would extend threads into the combustion chamber risks carbon and galling that will damage your threads in the head insert when removed.
The exposed threads can also create a hotspot leading to pre-ignition.

And the RN12YC is a resistor plug, which is undesireable (even for a chubblehead) unless you are running an electronic ignition.

If you are fouling out plugs enough to run out of spares, you have other problems.

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Re: Sparkplugs question


Post by dereborn » Fri Jan 16, 2004 4:12 pm

J12YC is what I run, the work just fine. A lott better than th yellow Accel crap someone sold me in the beginning... I tend to lean towards Cottens "No A-products" - policy

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Re: Sparkplugs question


Post by 57Kicker » Wed Jan 21, 2004 1:02 am

I paid $20 for a pair of H-D plugs at the local dealer and they worked fine....for about 50 miles then quit. Just plain QUIT! $%#@ing junk. I couldn't figure it out. All else seemed fine. Replaced with champions J12YC and they ran well with no complaints. The shop I bought them at wouldn't replace them or offer why they would quit. I still can't figure it out. I could understand one... but both?

that's my 2cents worth

What does work in a pan for plugs?

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Re: Sparkplugs question


Post by 57stroker » Wed Jan 21, 2004 7:58 am

Here is what I run:" onclick=";return false; Same price as Champion, and they seem to last longer.

It is NGK Part No. R5670-5 The stock number is 2298. NGK makes this specifically for Panheads. I've had good luck with them. Harley Davidson plugs are either Champions or Split Fires. I've seen Split Fires just quit for no reason. I have a Honda four stroke dirt bike ('84 XR500R). If you crash the bike or kill the motor when it is hot, Split Fire is the only plug I've seen that will get it started without waiting 1/2 hour for the motor to cool off.

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