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NGK

Iridium IX Spark Plug - 3521

1 / 5

NGK

Iridium IX Spark Plug - 3521

MSRP: $10.95

Price: $9.08 17% off!
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NGK Iridium IX Spark Plug - 3521
  • Heres the ultimate in spark plug technology and performance from the industry leader
  • The iridium electrode is a full 25 percent smaller than the platinum electrode and just 1/4 the size of a conventional nickel electrode
  • Ultra-small diameter center electrode reduces voltage requirement and extends ignition system life
  • New metal shell plating has enhanced anticorrosion qualities
  • Sold each
Specifications
Part #: CR9EIX
Mfg #: 3521
Heat Range 9
Thread 10 mm
Type Resistor
Units Each
Weight 0.12 lbs
Alternate/OEM Part Number(s):
3521, CR9EIX
UPC Code:
087295135211
Resources & Manuals
Instruction Manual 361.3 KiB
Fitment for NGK Iridium IX Spark Plug - 3521

Part CR9EIX fits the following machines

Aprilia
  • Mojito 125 2003-2005
  • Mojito Custom 125 2003-2005
Arctic Cat
  • Bearcat 7000 XT 2016-2018
  • Bearcat 7000 XT GS 2016-2018
  • M 7000 Limited Sno Pro w/153" Track 2016
  • M 7000 Limited Sno Pro w/162" Track 2016
  • M 7000 Sno Pro 2015
  • M 7000 Sno Pro w/153" Track 2016
  • M 7000 Sno Pro w/162" Track 2016
  • Pantera 7000 2015-2016, 2018
  • Pantera 7000 Limited 2015-2019
  • Pantera 7000 XT Limited 2016-2018
  • XF 7000 Cross Country 2015
  • XF 7000 Cross Country Sno Pro 2014-2015
  • XF 7000 CrossTour 2014-2018
  • XF 7000 CrossTrek 2016-2018
  • XF 7000 High Country Sno Pro 2015-2016
  • XF 7000 Limited Sno Pro 2014-2015
  • XF 7000 LXR 2014-2015
  • XF 7000 Sno Pro 2014-2015
  • ZR 7000 El Tigre 2015-2017
  • ZR 7000 Limited iACT w/137" Track 2019
  • ZR 7000 Limited Sno Pro 2014-2015
  • ZR 7000 Limited Sno Pro w/129" Track 2016
  • ZR 7000 Limited Sno Pro w/137" Track 2016
  • ZR 7000 Limited w/137" Track 2017-2019
  • ZR 7000 LXR 2014-2015
  • ZR 7000 LXR w/129" Track 2016-2017
  • ZR 7000 LXR w/137" Track 2016-2017
  • ZR 7000 RR 2015-2016
  • ZR 7000 Sno Pro 2014-2015
  • ZR 7000 Sno Pro w/129" Track 2016
  • ZR 7000 Sno Pro w/137" Track 2016-2018
  • ZR 7000 w/129" Track 2018
  • ZR 7000 w/137" Track 2018-2019
Ducati
  • ST3 2004-2005
Harley-Davidson
  • Electra Glide Standard - FLHT 2019-2020
  • Electra Glide Ultra Classic - FLHTCU 2017-2019
  • Electra Glide Ultra Limited - FLHTK 2017-2020
  • Electra Glide Ultra Limited CVO/SE - FLHTKSE 2017-2020
  • Electra Glide Ultra Limited Low - FLHTKL 2017-2019
  • Freewheeler - FLRT 2017-2020
  • Road Glide - FLTRX 2018-2020
  • Road Glide CVO/SE - FLTRXSE 2018-2019
  • Road Glide Limited - FLTRK 2020
  • Road Glide Special - FLTRXS 2017-2020
  • Road Glide Ultra - FLTRU 2017-2019
  • Road King - FLHR 2017-2020
  • Road King Police - FLHP 2017-2018
  • Road King Special - FLHRXS 2017-2020
  • Softail Breakout - FXBR 2018-2019
  • Softail Breakout 114 - FXBRS 2018-2020
  • Softail Deluxe - FLDE 2018-2020
  • Softail Fat Bob - FXFB 2018-2019
  • Softail Fat Bob 114 - FXFBS 2018-2020
  • Softail Fat Boy - FLFB 2018-2019
  • Softail Fat Boy 114 - FLFBS 2018-2020
  • Softail Heritage Classic - FLHC 2018-2020
  • Softail Heritage Classic 114 - FLHCS 2018-2020
  • Softail Low Rider - FXLR 2018-2020
  • Softail Low Rider S - FXLRS 2020
  • Softail Slim - FLSL 2018-2020
  • Softail Sport Glide - FLSB 2018-2020
  • Softail Street Bob - FXBB 2018-2020
  • Street - XG 500 2015-2020
  • Street - XG 750 2015-2020
  • Street Glide - FLHX 2017-2020
  • Street Glide CVO/SE - FLHXSE 2017-2020
  • Street Glide Special - FLHXS 2017-2020
  • Street Rod - XG 750A 2017-2020
  • Tri Glide Ultra Classic - FLHTCUTG 2017-2020
  • Tri-Glide CVO/SE - FLHTCUTGSE 2020
Kawasaki
  • ZR1100A 1993-1994
  • ZX1200C ZZ-R 2004-2005
  • ZX600E Ninja ZX-6 1993-2002
  • ZX600E ZZ-R 2003-2004
  • ZX600F Ninja ZX-6R 1995-1997
  • ZX600G Ninja ZX-6R 1998-1999
  • ZX600J Ninja ZX-6R 2000-2002
  • ZX600J ZZ-R 2005-2008
  • ZX600K Ninja ZX-6RR 2003
  • ZX600M Ninja ZX-6RR 2004
  • ZX600N Ninja ZX-6RR 2005-2006
  • ZX600P Ninja ZX-6R 2007-2008
  • ZX600R Ninja ZX-6R 2009-2012
  • ZX600R-A Ninja ZX-6R Monster Energy 2009
  • ZX636B Ninja ZX-6R 2003-2004
  • ZX636C Ninja ZX-6R 2005-2006
  • ZX636D Ninja ZX-6R 2006
  • ZX636E-F Ninja ZX-6R 2013-2018
  • ZX636E-F Ninja ZX-6R 30th Anniversary 2015
  • ZX636F-F Ninja ZX-6R ABS 2013-2018
  • ZX636F-F Ninja ZX-6R ABS 30th Anniversary 2015
  • ZX750L Ninja ZX-7 1993-1995
  • ZX750M Ninja ZX-7R 1993-1994
  • ZX750N Ninja ZX-7RR 1996-1997
  • ZX750P Ninja ZX-7R 1996-2003
Suzuki
  • DR-Z250 2001-2007
  • GSX1300R Hayabusa 1999-2007, 2011-2012
  • GSX1300RZ Hayabusa Limited Edition 2004-2006
  • GSX-R1000 2001-2006
  • GSX-R1000Z Mladin Replica Edition 2004
  • GSX-R1100W 1993, 1995-1998
  • GSX-R600 1998-2007, 2011-2012
  • GSX-R600M 2002
  • GSX-R600X 20th Anniversary 2005
  • GSX-R750 1996-2007
  • GSX-R750W 1994-1995
  • GSX-R750X 20th Anniversary 2005
  • RF600R 1994-1996
  • RF900R 1994-1997
  • VZ800 Marauder 1997
Yamaha
  • FX Nytro 2008-2014
  • FX Nytro MTX 2008-2010
  • FX Nytro MTX 40th Anniversary 2008
  • FX Nytro MTX SE w/153" track 2010-2012
  • FX Nytro MTX SE w/162" track 2010-2012
  • FX Nytro MTX w/153" track 2013-2014
  • FX Nytro MTX w/162" track 2013-2014
  • FX Nytro RTX 2008-2013
  • FX Nytro RTX 40th Anniversary 2008
  • FX Nytro RTX SE 2009-2010
  • FX Nytro RTX w/Reverse 2008
  • FX Nytro XTX 2009-2013
  • FX Nytro XTX 1.75 2013-2014
  • FZ600R FZ6R 2009-2017
  • FZ800N 2011-2013
  • FZR600R 1989-1999
  • FZS1000 FZ1 2001-2006, 2011-2015
  • RX Warrior 2004-2005
  • RX Warrior Limited Edition 2004-2005
  • RX-1 2003-2005
  • RX-1 ER 2003-2005
  • RX-1 ER Limited Edition 2003-2004
  • RX-1 Limited Edition 2003-2004
  • RX-1 Mountain 2003-2005
  • RX-1 Mountain Limited Edition 2003-2004
  • SR Viper BTX LE 2017
  • SR Viper LTX 2014, 2018-2019
  • SR Viper LTX DX 2015-2018
  • SR Viper LTX GT 2020
  • SR Viper LTX LE 2015-2017
  • SR Viper LTX LE 50th 2018
  • SR Viper LTX SE 2014-2017, 2020
  • SR Viper MTX 141 SE 2016
  • SR Viper MTX 153 2015-2016
  • SR Viper MTX 153 LE 2016
  • SR Viper MTX 153 SE 2015-2017
  • SR Viper MTX 162 2016
  • SR Viper MTX 162 LE 2015-2016
  • SR Viper MTX 162 SE 2015-2017
  • SR Viper RTX 2018
  • SR Viper RTX DX 2015-2017
  • SR Viper RTX LE 2015-2016
  • SR Viper RTX SE 2014-2017
  • SR Viper STX 137 DX 2016-2017
  • SR Viper STX 146 DX 2016-2017
  • SR Viper STX DX 2015
  • SR Viper XTX LE 2015-2016
  • SR Viper XTX SE 2014-2018
  • TT-R250 1999-2006
  • WR250F 2008-2009, 2011-2013
  • WR450F 2007-2009, 2011
  • YZ450F 2011-2013
  • YZF600R 1994-2007
  • YZF750R 1994, 1996-1998
  • YZF-R1 1000 1998-2003
  • YZF-R1S 1000 Champions Limited Edition 2001
Reviews & Questions
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Browse 1 question Browse 1 question and 1 answer
What is the Gap?
A shopper on Jan 15, 2018
BEST ANSWER: Varies according to the Manufacturer of the bike. Check your owner/service manual.
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4.3 / 5.0
7 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
5
1
0
0
1
Finish
5.0 / 5
Fit
4.6 / 5
Quality
5.0 / 5
Style
4.5 / 5
Value
4.8 / 5
Would you recommend this product?
Yes (3)
Fit
5 / 5
Quality
5 / 5
Style
4 / 5
Value
5 / 5
Good solid value
Nice plugs, the gaps were set right out of the box. Fit perfect and expect a long life out of them. Quality design.
July 20, 2010
Fit
5 / 5
Quality
5 / 5
Style
5 / 5
Value
5 / 5
No Review Title Entered By User
Bike seems to run better. (I had 15 year old plugs!)
Will see how these last.
April 12, 2011
Fit
5 / 5
Quality
5 / 5
Style
5 / 5
Value
5 / 5
No Review Title Entered By User
No Review Text Entered By User
March 3, 2013
Finish
5 / 5
Fit
4 / 5
Quality
5 / 5
Value
5 / 5
Would you recommend this product?
Yes
2015 Street 750
Hi all. Put a set of these in my Street 750 about 6K Miles ago. So far so good. Bought another set for the next Tune-Up. I gave these 4 stars on "Fit" Reason being, The Factory plugs Threads are a little longer. 1 Threads worth. Maybe a problem? Wont know until I remove them. These are the ones NGK told me to use.
December 31, 2016
Trenton, NJ
Purchased
 over 3 years ago
Ride:
2018 HD Custom 1200
Would you recommend this product?
Yes
The ne plus ultra of plugs
This is the plug I replace the standard plugs with.
May 5, 2019
Bluffton, IN
Purchased
 11 months ago
Ride:
Many
Fit
4 / 5
Quality
5 / 5
Style
4 / 5
Value
4 / 5
No Review Title Entered By User
No Review Text Entered By User
September 29, 2009
Columbia, MD
Would you recommend this product?
Yes
It made me sad
This does not fit on a 2007 GSX-R 600
August 28, 2018
Purchased
 1 year ago