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Recommended spark plug ?

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Old Jun 29, 2014 | 11:48 AM
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Default Recommended spark plug ?
Newbie. 1989 FLHS. I believe stock with exception of S&S carb.

Bought bike with Champion 5R6A plugs. This is also plug called for in service manual.

Just curious if anyone recommends any different plug specification (hotter or colder, iridium, etc - don't want to start a "plug brand debate")

Thanks !
 
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Old Jun 29, 2014 | 12:00 PM
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I've always used the H-D 5R6A (Champion RN12YC) myself. Is there some reason you want to use something else?
 
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Old Jun 29, 2014 | 12:19 PM
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First had no spark - bad coil - replaced.

Now bike is running rough - bogs down on acceleration and sometimes seems to backfire back through carb. Thought next step should be plugs and wires - didn't know if S&S carb would affected recommended plug.

Any brand of wires recommended and website to buy ?

I'm on a budget (read:cheap)......

Thanks !
 
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Old Jun 29, 2014 | 12:38 PM
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This the same bike that's been sitting a year????

I'd be checking the intake manifold seals before I started messing around with the spark plugs.
 
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Old Jun 29, 2014 | 01:04 PM
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in my shop we only use ( iridium sparkplugs ) they last 100,000 miles and perform at a much better rate than the fishing pole weight a champion plug is
 
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Old Jun 29, 2014 | 02:33 PM
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Same bike that has been sitting - I'll check intake seals first - thanks.
 
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Old Jun 29, 2014 | 04:22 PM
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Originally Posted by johnjzjz
in my shop we only use ( iridium sparkplugs ) they last 100,000 miles and perform at a much better rate than the fishing pole weight a champion plug is

Same here......
 
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Old Jun 30, 2014 | 11:53 PM
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Originally Posted by johnjzjz
in my shop we only use ( iridium sparkplugs ) they last 100,000 miles and perform at a much better rate than the fishing pole weight a champion plug is
Well this showed up with perfect timing. Lol. Now that I have the ole pig jetted pretty well. What part number and brand plug do u rocommend.john
 
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Old Jul 1, 2014 | 12:03 AM
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Here is a good link when needing plug advice http://www.ngksparkplugs.com/part_fi...es/default.asp
 
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Old Jul 1, 2014 | 12:10 AM
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hands down NGK no one makes a better spark plug.
BPR5EIX-11 is the plug I use in my evo.
 
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