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K&N

K&N Cold Air Intake System: Powersports High-Flow Air Filter, RK-3951

Based on 44 reviews
Condition: New
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$231.83
Save $83.16 was $314.99

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Availability: 15 left in stock
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Arrives Tuesday, Nov 3
Order within 20 hours and 37 minutes

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At a glance

Condition
New
Model
RK-3951
Weight
4.7 lb
Product Grade
Performance Part
Fit Type
Vehicle Specific Fit
Item Type Name
Intake System (Harley Davidson)
In the box
Air Filter^Back Plate^Air Scoop^Air Scoop Base^Breather Bolt (2)^Literature Pack^Parts Kit

Features 4

  • Increased Horsepower: Guaranteed to increase horsepower, helping unlock greater performance from your engine.
  • Enhanced Driving Experience: Improves throttle response and improved engine sound.
  • Premium Construction: Built with premium intake materials and a durable, high-quality finish designed for lasting performance.
  • Washable & Reusable Air Filter: Includes a High-Flow Air Filter that can go up to 100,000 miles before cleaning under normal highway driving conditions.

Description

K&N is the inventor of the Air Intake System and has over 50 years of experience in the performance filtration industry. Proudly designed and manufactured in the USA, this premium cold air intake system is specifically designed for your vehicle and is dyno tested to provide a guaranteed increase in horsepower. It features a high flow intake tube, custom heat shield, and oversized K&N Washable High-Flow Cotton Air Filter for ultimate airflow. This Intake system replaces the restrictive OEM air box to provide an improved driving experience for daily driving or towing. It installs easily in about 60 minutes and is backed by a No-Hassle Lifetime Limited Warranty and will not void your factory warranty.Compatible Vehicles:2007-2017 HARLEY DAVIDSON FXDB Street Bob2008-2017 HARLEY DAVIDSON FXDF Fat Bob2007-2017 HARLEY DAVIDSON FXDL Dyna Low Rider2014-2017 HARLEY DAVIDSON FXDL Low Rider2007-2017 HARLEY DAVIDSON FXDWG Dyna Wide Glide2013-2016 HARLEY DAVIDSON FLD Switchback2012-2015 HARLEY DAVIDSON FLS Softail Slim2007-2015 HARLEY DAVIDSON FLSTC Heritage Softail Classic2007-2015 HARLEY DAVIDSON FLSTF Fat Boy2010-2015 HARLEY DAVIDSON FLSTFB Softail Fat Boy Lo2007-2015 HARLEY DAVIDSON FLSTN Softail Deluxe2014-2015 HARLEY DAVIDSON FXSB Breakout2007-2014 HARLEY DAVIDSON FXDC Super Glide Custom2011-2013 HARLEY DAVIDSON FXS Blackline2008-2011 HARLEY DAVIDSON FLSTSB Softail Cross Bones2008-2011 HARLEY DAVIDSON FXCWC Rocker C2007-2010 HARLEY DAVIDSON FXD Dyna Super Glide2007-2010 HARLEY DAVIDSON FXSTB Night Train2007-2010 HARLEY DAVIDSON FXSTC Softail Custom2008-2009 HARLEY DAVIDSON FXCW Rocker2007-2009 HARLEY DAVIDSON FXST Softail Standard2007 HARLEY DAVIDSON FLHR Road King2007 HARLEY DAVIDSON FLHRC Road King Classic2007 HARLEY DAVIDSON FLHRS Road King Custom2007 HARLEY DAVIDSON FLHT Electra Glide Standard2007 HARLEY DAVIDSON FLHTC Electra Glide Classic2007 HARLEY DAVIDSON FLHTCU Ultra Classic Electra Glide2007 HARLEY DAVIDSON FLHX Street Glide2007 HARLEY DAVIDSON FLSTSC Softail Springer Classic2007 HARLEY DAVIDSON FLTR Road Glide2007 HARLEY DAVIDSON FXSTD Softail Deuce2002-2006 HARLEY DAVIDSON FLHRCI Road King Classic F/I2003-2006 HARLEY DAVIDSON FLHRI Road King F/I2004-2006 HARLEY DAVIDSON FLHRSI Road King Custom F/I2002-2006 HARLEY DAVIDSON FLHTCI Electra Glide Classic F/I2002-2006 HARLEY DAVIDSON FLHTCUI Electra Glide Ultra Classic F/I2003-2006 HARLEY DAVIDSON FLHTI Electra Glide Standard F/I2006 HARLEY DAVIDSON FLHXI Street Glide F/I2002-2006 HARLEY DAVIDSON FLSTCI Heritage Softail Classic F/I2001-2006 HARLEY DAVIDSON FLSTFI Fat Boy F/I2006 HARLEY DAVIDSON FLSTI Heritage Softail F/I2005-2006 HARLEY DAVIDSON FLSTNI Softail Deluxe F/I2005-2006 HARLEY DAVIDSON FLSTSCI Softail Springer Classic F/I

Specs 18

Product Grade Performance Part
Brand K&N
Fit Type Vehicle Specific Fit
OEM Part Number RK-3951
Number of Items 1
Brand Name K&N
Model Number RK-3951
OEM Equivalent Part Number RK-3951

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Nov 3

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


It works for me
Easy swap out performs great looks good excellent finish to my stage 1 on my 08 Electra Glide ultra classic it does stick out a bit further than the factory one does I'm 6 foot so it doesn't bother me but someone with shorter legs might not like it
Reviewed in the United States on April 8, 2024 by Augie Ramos

Fits perfectly! Fits perfectly!
Fits perfectly. Just have to pay attention to the mounting screws for the backer plate vs. cover. Love the sucking sound when I open the throttle...
Reviewed in the United States on October 11, 2025 Reviewed in the United States on October 11, 2025 by Roger

Looks great Looks great
It was easy to install works great !
Reviewed in the United States on July 31, 2024 Reviewed in the United States on July 31, 2024 by Tommy Gee

Awesome look.
What can I say? This is a K&N product It works perfectly and looks great thank you.
Reviewed in the United States on May 11, 2025 by The amp is absolutely wonderful. It works perfect on a 2016 Street Glide special under the fairing.!

Pretty straight forward. Pretty straight forward.
Easy to install and I’m just hoping I don’t have to “tune” my 2008 streetglide. 106”
Reviewed in the United States on May 16, 2023 Reviewed in the United States on May 16, 2023 by Rox

Air intake Air intake
Wow! Great product, amazing look, fit perfectly.
Reviewed in the United States on July 5, 2023 Reviewed in the United States on July 5, 2023 by Arthur,N.Rumrill

Two Stars
No send it back
Reviewed in the United States on July 23, 2017 by Dnnorm

Love the look but for some reason it didn't fit ...
Love the look but for some reason it didn't fit my bike I ad to make spacers for it
Reviewed in the United States on November 10, 2017 by Stephane Mousse
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