Question about 2003 Harley Davidson FXSTD Softail Deuce

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Spark Plugs What spark plugs are most people using? I replaced my Harley Brand plugs-6R12? with NGK standard plugs. The reason I replaced them is because the guy I bought the bike from said he had not replaced them for a while. My bike now sounds different and doesn't seem to run as good. Platinum or performance plugs the way to go I guess?

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Stick with the stock HD plugs because of the ion sensing.

Posted on Nov 20, 2008


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What is the equivalent to a 5r6a ?

If you type this question into google you will get several equivalents. You may find questions like this are more quickly answered using google rather than waiting for Fixya answers

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What spark plug is used in a 2003 harley davidson flhrci road king

if it is the 88 cubic inch engine... this should be the correct ngk plug number, if you prefer another brand any parts house can cross the number for you. NGK Standard BPR5ES-11 Spark Plug

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Spark plug gap settings chart

If the plugs cannot be cleaned, replace them with No. 6R12 spark plugs. Check the electrode gap with a wire-type feeler gauge. Bend the outside of the electrode so only a slight drag on the gauge is felt when passing it between the electrodes. The proper gap measurement is 0.038-0.043 in. (0.97-1.09 mm).

Aug 09, 2014 | 2006 Harley Davidson FXST Softail Standard

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Ngk spark plugs gap chart

spark plug HD number. 6R12
Gap. 0.038-0.043 in. (0.97-1.09mm)

Jul 28, 2014 | Harley Davidson FLSTC Heritage Softail...

1 Answer

1972 shovel what type of spark plug can i use other than harley and what is the gap

Best to use Harley plugs

If the plugs require cleaning between tune-ups, proceed by degreasing the firing end of spark plug using ELECTRICAL CONTACT CLEANER and then dry plug with compressed air. THEN using a thin file flatten the spark plug electrodes because a spark plug with sharp edges on its electrodes requires 25-40% less firing voltage than one with rounded edges. If the plugs cannot be cleaned, replace with them with 6R12 spark plugs. Check the electrode gap with a wire-type feeler gauge and bend the outside of the electrode so only a slight drag on the gauge is felt when passing it between the electrodes. Proper gap measurement is 0.038-0.043 in. (0.97-1.09 mm). Check the condition of the cylinder head and plug threads and if necessary remove deposits by applying penetrating oil and clean them out with a thread chaser. Apply a good sensor safe ANTI-SEIZE to the plugs and then install and tighten them to 12-18 ft-lbs (16.3-24.4 Nm).

May 31, 2014 | Harley Davidson Harley-Davidson Motorcycle...

1 Answer

2006 FXSTD Spark plug gap?

Hi Anonymous, HD 6R12 spark plugs are gapped at .040"
Good luck

Btw, I’m available to help over the phone in case u need at

Apr 16, 2012 | 2006 Harley Davidson FXSTDI Softail Deuce

1 Answer

Im new in the harley world what spark plugs should i run in my 2002 roadking it is efi

Has this motorcycle been modified, the specs for a 2002 FLHRCI claim that it is naturally aspirated
(has a carb not efi)? If it has not been modified then my cross reference guide says the following are a replacements for the OEM part: accel Y2418P, Champion RA8HC, NGK 3932, NGK 6046, or HD 6R12... If the Engine has been modified, or replaced then these OEM plugs may not apply...

Aug 10, 2011 | 2002 Harley Davidson FLHRCI Road King...

1 Answer

What size spark plugs do I need for my 2001 Harley Softail Standard

H-D 6R12 or equilivent.

Personally, I prefer NGK spark plugs. I've had the best luck and longest life out of them in my Evo.

Good Luck

Sep 22, 2010 | 2001 Harley Davidson FXST Softail Standard

1 Answer

What are the correct spark plugs for a 1991 fxsts harley?

The correct Harley-Davidson spark plug is the 5R6A. I prefer the NGK BPR5ES-11. Champion Copper Plus-RN12YC Autolite standard 4265 Autolite Platinum-AP4265DP2 Most any automotive parts house has a spark plug fitment book.

Dec 10, 2009 | 2005 Harley Davidson FXSTS - FXSTSI...

2 Answers

What type and number is the best Spark plug to run in this engine 2002 twin cam

Your bike comes from the factory with the HD Standard 6R12 spark plug. I would recommend running with this plug.
Here are some other options:

Plug Manufacturer TC88/95 Engine Plug Gap .040" H-D Standard 6R12 H-D Gold 6R12G H-D Platinum 6R12PP Champion RA8HC Autolite 4164 Autolite Platinum AP4164DP2 ACCEL 2418
Y2418P Splitfire SF416D Screamin Eagle EX12S
EX12P ACDelco NGK DCPR7E Bosch Denso Iridium IXU22

Jun 08, 2009 | 2002 Harley Davidson FLHT Electra Glide...

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