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Custom Assemblies > Intake System-Harley Davidson

 List Price: $261.39
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RK-3931
 
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K&N Air Cleaner Assemblies are designed to get more horsepower from your Harley-Davidson® motorcycle. These air cleaner assemblies replace the stock air filter and backplate with an oversized K&N Air Filter and custom aluminum backing plate. These assemblies utilizes the stock cover to maintain stock appearance. [MORE]
  • Designed to increase horsepower & torque
  • Dyno-tuned velocity stack
  • Excellent Air Filtration
  • Washable and reusable lifetime air filter
  • Not legal for highway use in states adopting California emission regulations


Product Specifications 
Estimated Horsepower Gain:6.54 HP @ 5100 RPM
Air Filter Color:Red
Air Filter Height:2.125 in (54 mm)
Air Filter Material:Cotton Gauze
Air Filter Outlet Shape:Not Flanged
Air Filter Shape:Unique
California Restricted:Not legal for sale or use in California
Clamp Material:No Clamps Required
Clamp Style:No Clamps Required
Color:Red
Filter Material:Cotton Gauze
Inlet Diameter:2.406 in (61 mm)
Intake Pipe Ports:All intake tube ports needed for the specified applications are included
Mass Air Flow Sensor Adapter Included:Mass Air Flow Sensor Adapter Included When Required
Mounting Hardware Included:Yes
Neck Flange:2.406 in (61 mm)
Overall Height:2.5 in (64 mm)
Part Number:RK-3931
Product Box Height:4.88 in (124 mm)
Product Box Length:11.75 in (298 mm)
Product Box Width:9.5 in (241 mm)
Product Style:Motorcycle Intake System
Replacement Filter:E-3975
Size:9 Inch
Street Legal In All US States:No
Style:Teardrop
Top Material/Finish:Aluminum
Top Style:Metal
Total Height:2.5 in (64 mm)
TUV Approved (Europe):No
Vacuum Tubing Included:No
Weight:3.1 lb (1.4 kg)

Horsepower gains based on similar vehicle dynamometer test. Results will vary.


Customer Feedback      Be the first to review part RK-3931

Best filters ever. Run them in all my vehicles including my Harley Davidson Motorcycle. Saved a ton of $$$ too by not having to purchase replacement paper filters every time.
Bill Sleeper, Altadena, California
All of my vehicles including my Harley Davidson have K&N Filters installed. They perform without equal.
Robert W.Garcia Sr., Paradise, Texas
I have used K&N products for several years as a ship's engineer. I am now retired and still own the 1988 Harley Davidson FLST I bought new in '87. I also am still using one of the first Screamin Eagle CV carbs. No one makes the correct air filter, so I went back home to K&N for a universal filter that I knew would not only deliver the air flow necessary but would look good as well.
John Sayers, Lecanto, Florida