Description
NGK Spark Plugs
This is the workhorse, the plug that is at the heart of smooth-running engines around the world. These are great, all-around, spark plugs that we use on the bikes in our shop as well as our own.
- OEM quality
- Triple-gasket sealing process
- Consistent performance
- Plug of choice at Imzz Elite
**Each order includes 2 spark plugs
5 THINGS YOU SHOULD KNOW ABOUT SPARK PLUGS
1. Anti-seize
NGK spark plugs feature what is known as trivalent plating. This silver-or-chrome colored finish on the threads is designed to provide corrosion resistance against moisture and chemicals. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without the use of anti-seize. NGK tech support has received a number of tech calls from installers who have over-tightened spark plugs because of the use of anti-seize. Anti-seize compound can act as a lubricant altering torque values up to 20 percent, increasing the risk of spark plug thread breakage.
2. Corona stain
Corona stain is observed as a light brown or tan discoloration above the hex (located on the ceramic body of the spark plug). Corona stain is created by oil or dirt particles surrounding the spark plug. Spark plugs create a high amount of static electricity as they fire, attracting these particles to the exposed ceramic between the plug boot and the hex. Corona stain is completely normal and should not be mistaken for exhaust gas blow-by or broken seals inside the spark plug.
3. Gapping fine-wire spark plugs
In the late 1980s, when fine-wire spark plugs first appeared, installers used incorrect gap tools and procedures resulting in bent or broken-off firing electrodes. As a result, many people assumed that one cannot adjust the gap on a precious metal plug. While most NGK spark plugs are pre-gapped, there are instances where the gap requires modification. NGK recommends a wire-style or feeler gage gap tool, which can adjust the gap without prying against the center electrode. NGK also recommends adjusting the gap no more than +/- 0.008” from the preset gap.
4. Torque
Torque is critical in the plug’s ability to dissipate heat and perform properly. Always follow the manufacturer’s recommended torque specification. An under-torqued spark plug can lead to excessive vibration and improper heat dissipation, causing spark plug and/or engine damage. An over-torqued spark plug may cause thread damage or breakage, or compromise internal seals within the spark plug, leading to improper heat dissipation or exhaust gas blow-by.
5.“Copper plugs”
“Copper spark plugs” is a term mistakenly used for a standard material spark plug. A standard material spark plug traditionally uses a nickel-alloy outer material fused to a copper core. Almost all spark plugs use a copper core center to conduct the electricity, jump the gap, and promote heat dissipation. However, as an outer electrode material, copper would not be a good choice, as it is soft and has a low melting point (resulting in a plug that would last minutes, not miles). Nearly all NGK spark plugs, including precious metals iridium and platinum, have a copper core. When one talks in terms of nickel alloys, platinum and iridium, one is referring to its durability, or how long a spark plug will last before it needs to be replaced. However, when one talks about copper, he or she is referring to its ability to conduct electricity that is needed to fire across the gap and ignite the air-fuel mixture.
HOW DO I INSTALL SPARK PLUGS CORRECTLY?
A: It is essential to tighten a spark plug to the specified turning angle or torque setting. First, screw in the plug finger tight until the gasket meets the cylinder head. Then seat the plug/gasket with a torque or turning angle wrench as specified in the chart below.
|
Spark plug type |
Thread Diameter |
Cast Iron Cylinder Head (lb-ft.) |
Aluminum Cylinder Head (lb-ft.) |
|
Flat seat type (with gasket) |
18 ø mm |
25.3~32.5
|
25.3~32.5 |
|
|
14 ø mm |
18.0~25.3 |
18.0~21.6 |
|
|
12 ø mm |
10.8~18.0 |
10.8~14.5 |
|
|
10 ø mm |
7.2~10.8 |
7.2~8.7 |
|
|
8 ø mm |
— |
5.8~7.2 |
|
Conical seat type (without gasket) |
18 ø mm |
14.5~21.6 |
14.5~21.6 |
|
Conical seat type (without gasket) |
14 ø mm |
10.8~18.0 |
7.2~14.5 |
This is very important, as excessive tightening of a spark plug can cause breakage of the metal shell and damage to the interior seals. At the same time, insufficient tightening can lead to overheating of the spark plug and potential detonation.
Fitment Guide
99-17 Twin Cam fits:
2011 – 2013 Harley-Davidson Blackline FXS
2013 – 2017 Harley-Davidson Breakout FXSB
1999 – 2000 Harley-Davidson Dyna Convertible FXDS-CONV
1999 – 2013 Harley-Davidson Electra Glide Classic EFI FLHTCI
1999 – 2005 Harley-Davidson Electra Glide Classic FLHTC
2003 – 2009 Harley-Davidson Electra Glide Standard EFI FLHTI
1999 – 2006 Harley-Davidson Electra Glide Standard FLHT
1999 – 2016 Harley-Davidson Electra Glide Ultra Classic EFI FLHTCUI
1999 Harley-Davidson Electra Glide Ultra Classic FLHTCU
2015 – 2016 Harley-Davidson Electra Glide Ultra Classic Low FLHTCUL
2010 – 2016 Harley-Davidson Electra Glide Ultra Limited FLHTK
2015 – 2016 Harley-Davidson Electra Glide Ultra Limited Low FLHTKL
2008 – 2017 Harley-Davidson Fat Bob FXDF
2010 – 2016 Harley-Davidson Fat Boy Lo FLSTFB
2016 – 2017 Harley-Davidson Fat Boy S FLSTFBS
2015 – 2016 Harley-Davidson Freewheeler FLRT
2007 – 2009 Harley-Davidson Low Rider EFI FXDL
2015 – 2016 Harley-Davidson Low Rider EFI FXDL
1999 – 2005 Harley-Davidson Low Rider FXDL
2016 – 2017 Harley-Davidson Low Rider S FXDLS
1999 – 2009 Harley-Davidson Road Glide EFI FLTR
2010 – 2013 Harley-Davidson Road Glide Custom FLTRX
2015 – 2016 Harley-Davidson Road Glide Custom FLTRX
1999 – 2002 Harley-Davidson Road Glide FLTR
2015 – 2016 Harley-Davidson Road Glide Special FLTRXS
2011 – 2013 Harley-Davidson Road Glide Ultra FLTRU
2016 Harley-Davidson Road Glide Ultra FLTRU
1999 – 2006 Harley-Davidson Road King Classic EFI FLHRC
2004 – 2007 Harley-Davidson Road King Custom EFI FLHRS
2004 – 2006 Harley-Davidson Road King Custom FLHRS
1999 – 2001 Harley-Davidson Road King EFI FLHR
2007 – 2016 Harley-Davidson Road King EFI FLHR
1999 – 2006 Harley-Davidson Road King FLHR
2008 – 2011 Harley-Davidson Softail Cross Bones FLSTSB
2007 – 2010 Harley-Davidson Softail Custom EFI FXSTC
2005 – 2017 Harley-Davidson Softail Deluxe EFI FLSTNI
2005 – 2006 Harley-Davidson Softail Deluxe FLSTN
2001 – 2007 Harley-Davidson Softail Deuce EFI FXSTDI
2000 – 2006 Harley-Davidson Softail Deuce FXSTD
2001 – 2017 Harley-Davidson Softail Fat Boy EFI FLSTFI
2000 – 2006 Harley-Davidson Softail Fat Boy FLSTF
2001 – 2017 Harley-Davidson Softail Heritage Classic EFI FLSTCI
2000 – 2006 Harley-Davidson Softail Heritage Classic FLSTC
2006 Harley-Davidson Softail Heritage EFI FLSTI
2006 Harley-Davidson Softail Heritage FLST
2001 – 2003 Harley-Davidson Softail Heritage Springer EFI FLSTSI
2000 – 2003 Harley-Davidson Softail Heritage Springer FLSTS
2001 – 2009 Harley-Davidson Softail Night Train EFI FXSTBI
2000 – 2006 Harley-Davidson Softail Night Train FXSTB
2008 – 2011 Harley-Davidson Softail Rocker C FXCWC
2008 – 2009 Harley-Davidson Softail Rocker FXCW
2012 – 2017 Harley-Davidson Softail Slim FLS
2016 – 2017 Harley-Davidson Softail Slim S FLSS
2005 – 2007 Harley-Davidson Softail Springer Classic EFI FLSTSCI
2005 – 2006 Harley-Davidson Softail Springer Classic FLSTSC
2001 – 2006 Harley-Davidson Softail Springer EFI FXSTSI
2000 – 2006 Harley-Davidson Softail Springer FXSTS
2001 – 2007 Harley-Davidson Softail Standard EFI FXSTI
2000 – 2006 Harley-Davidson Softail Standard FXST
2006 – 2017 Harley-Davidson Street Bob FXDB
2006 – 2016 Harley-Davidson Street Glide EFI FLHX
2006 Harley-Davidson Street Glide FLHX
2014 – 2016 Harley-Davidson Street Glide Special FLHXS
2010 – 2011 Harley-Davidson Street Glide Trike FLHXXX
2005 – 2014 Harley-Davidson Super Glide Custom EFI FXDCI
2005 Harley-Davidson Super Glide Custom FXDC
2004 – 2010 Harley-Davidson Super Glide EFI FXDI
1999 – 2005 Harley-Davidson Super Glide FXD
2006 Harley-Davidson Super Glide FXD35
2004 – 2005 Harley-Davidson Super Glide Sport EFI FXDXI
1999 – 2005 Harley-Davidson Super Glide Sport FXDX
2001 – 2003 Harley-Davidson Super Glide T-Sport FXDXT
2012 – 2016 Harley-Davidson Switchback FLD
2009 – 2016 Harley-Davidson Tri Glide Ultra Classic FLHTCUTG
2004 – 2008 Harley-Davidson Wide Glide EFI FXDWGI
2010 – 2017 Harley-Davidson Wide Glide EFI FXDWGI
1999 – 2005 Harley-Davidson Wide Glide FXDWG
17-20 M8 fits:
2018 Harley-Davidson Breakout – FXBR
2018 Harley-Davidson Breakout 114 – FXBRS
2018 Harley-Davidson Deluxe – FLDE
2017 – 2018 Harley-Davidson Electra Glide Ultra Classic EFI FLHTCUI
2017 – 2019 Harley-Davidson Electra Glide Ultra Limited FLHTK
2017 – 2019 Harley-Davidson Electra Glide Ultra Limited Low FLHTKL
2018 Harley-Davidson Fat Bob – FXFB
2018 Harley-Davidson Fat Bob 114 – FXFBS
2018 Harley-Davidson Fat Boy – FLFB
2018 Harley-Davidson Fat Boy 114 – FLFBS
2017 – 2018 Harley-Davidson Freewheeler FLRT
2018 Harley-Davidson Heritage Classic – FLHC
2018 Harley-Davidson Heritage Classic 114 – FLHCS
2018 Harley-Davidson Low Rider – FXLR
2017 – 2018 Harley-Davidson Road Glide Custom FLTRX
2017 – 2019 Harley-Davidson Road Glide Special FLTRXS
2017 – 2018 Harley-Davidson Road Glide Ultra FLTRU
2017 – 2019 Harley-Davidson Road King EFI FLHR
2018 Harley-Davidson Road King Special FLHRXS
2018 Harley-Davidson Softail Breakout 114 FXBRS
2018 Harley-Davidson Softail Breakout FXBR
2018 Harley-Davidson Softail Deluxe FLDE
2018 Harley-Davidson Softail Fat Bob 114 FXFBS
2018 Harley-Davidson Softail Fat Bob FXFB
2018 Harley-Davidson Softail Fat Boy 114 FLFBS
2018 Harley-Davidson Softail Fat Boy FLFB
2018 Harley-Davidson Softail Heritage Classic 114 FLHCS
2018 Harley-Davidson Softail Heritage Classic FLHC
2018 Harley-Davidson Softail Low Rider FXLR
2018 Harley-Davidson Softail Slim – FLSL
2018 Harley-Davidson Softail Slim FLSL
2018 Harley-Davidson Softail Sport Glide FLSB
2018 Harley-Davidson Softail Street Bob FXBB
2018 Harley-Davidson Sport Glide – FLSB
2017 – 2019 Harley-Davidson Street 500 XG
2017 – 2019 Harley-Davidson Street 750 XG
2018 Harley-Davidson Street Bob – FXBB
2017 – 2019 Harley-Davidson Street Glide EFI FLHX
2017 – 2018 Harley-Davidson Street Glide Special FLHXS
2017 – 2018 Harley-Davidson Street Rod 750 A XG
2017 – 2018 Harley-Davidson Tri Glide Ultra Classic FLHTCUTG
86-20 XL fits:
2007 – 2018 Harley-Davidson 1200 Custom EFI XLC
1996 – 2006 Harley-Davidson 1200 Custom XLC
2006 – 2011 Harley-Davidson 1200 Low EFI XLL
2006 Harley-Davidson 1200 Low XLL
2007 – 2012 Harley-Davidson 1200 Nightster XLN
2007 – 2008 Harley-Davidson 1200 Roadster EFI XLR
2016 – 2018 Harley-Davidson 1200 Roadster XLCX
2004 – 2006 Harley-Davidson 1200 Roadster XLR
1996 – 2003 Harley-Davidson 1200 Sport XLS
2005 Harley-Davidson 15th Anniversary Fat Boy FLSTF
2007 – 2009 Harley-Davidson 883 Custom EFI XLC
1999 – 2006 Harley-Davidson 883 Custom XLC
1986 – 1995 Harley-Davidson 883 Deluxe XLH
2007 – 2008 Harley-Davidson 883 EFI XL
1987 – 2003 Harley-Davidson 883 Hugger XLH
2007 – 2010 Harley-Davidson 883 Low EFI XLL
2014 Harley-Davidson 883 Low EFI XLL
2017 – 2018 Harley-Davidson 883 Low EFI XLL
2005 – 2006 Harley-Davidson 883 Low XLL
2007 Harley-Davidson 883 Roadster EFI XLR
2002 – 2003 Harley-Davidson 883 Roadster XLR
2005 – 2006 Harley-Davidson 883 Roadster XLR
2011 – 2016 Harley-Davidson 883 SuperLow XLL
2004 – 2006 Harley-Davidson 883 XL
2018 Harley-Davidson XL 1200NS – Iron 1200
2018 Harley-Davidson XL 1200XS – 48 Special
2014 – 2017 Harley-Davidson SuperLow 1200 XLT
1986 – 1987 Harley-Davidson Sportster 1100 XLH
2011 – 2012 Harley-Davidson Sportster 1200 X XR
2007 Harley-Davidson Sportster 1200 XL 50
1988 – 2003 Harley-Davidson Sportster 1200 XLH
2009 – 2010 Harley-Davidson Sportster 1200 XR
1986 – 2003 Harley-Davidson Sportster 883 XLH
2010 – 2018 Harley-Davidson Sportster Forty-Eight XLX
2012 – 2016 Harley-Davidson Sportster Seventy-Two XLV
2009 – 2018 Harley-Davidson Iron 883 XLN
Michael M. (verified owner) –
The best