Arlen Ness 81-018

• Beveled® Style Cover Kit 
• 90° Forward-Facing Intake Design 
• Patented Hidden Breather Technology 
• High performance black oiled cotton air filter  
• Massive filter design & inverted filter top for more airflow   
• Increased Horsepower, torque & mileage 
• Excellent legroom 
• Aluminum backing plate and elbow 
• Chrome finish 

ALUMINUM ONE-PIECE BACKING PLATE:

• Made from aluminum 
• Our patented hidden breather technology is o-ringed at the heads and exist out the mouth of the injector/carb to provide efficient engine breathing, eliminating the need for any external hoses or hardware for a virtually closed loop system 
• Smooth and sculpted backing plate shape wraps around the throttle body for excellent leg room 
• Milwaukee-Eight® (M8) engine applications include a formed throttle servo cover that is finished in black powdercoat
• Triple-bolt flush mount elbow mounting design 
• Will not work with factory bagger lower fairings (lowers) 

HIGH PERFORMANCE AIR FILTER

• High performance black oiled cotton air filter
• More filter surface area then any other 90° degree air cleaner kit on the market, air is pulled in from the sides of the filter as well as the front through the inverted pleated top 
• Chrome plated filter top with Arlen Ness® logo 
• Forged billet air filter covers are available, covers can be added to any Monster Sucker® intake 

ALUMINUM AIR CLEANER ELBOW & OUTER COVER

• 90° aluminum single-piece design
• Hidden air filter clamping area for no exposed clamps resulting in a clean look 
• Outer decorative cover is CNC machined from forged billet aluminum 
• Cover features an inverted top to direct airflow into the top of the filter 

BACKING PLATE ASSEMBLY (FITMENT SPECIFIC)

08-16 FLT / 16-17 SOFTAIL & FXDLS (FBW)

Backing Plate: 81-005-1C

Breather Bolts: 81-005-2C (2)

Breather Bolt Copper Washers: H-070 (2)

Breather Bolt O-Rings (2pack): H-024

Throttle Body Gasket: 18-500-5

Throttle Body Hardware, 1/4-20 x 3/4: H-656Z (3)

00-17 TWIN CAM (EXC. FBW)

Backing Plate: 81-000-1C

Breather Bolts: 81-005-2C

Breather Bolt Copper Washers:H-070

Breather Bolt O-Rings (2pack): H-024

Throttle Body Gasket: 18-510-2

Throttle Body Hardware, 1/4-20 x 3/4: H-656Z (3)

Throttle Body Elbow Intake Cover: 81-005-3B

Throttle Body Elbow Cover bolts 6-32x14 Flathead Allen: H504S (2)

91-UP XL SPORTSTER

Backing Plate: 81-010-1C

Breather Bolts: 81-010-3C (2)

Breather Bolt Copper Washers: H-070 (2)

Breather Bolt O-Rings (2pack): H-024

Manifold Spacer: 18-492-2

Throttle Body Gasket: 18-500-5

Throttle Body Hardware, 1/4-20 x 3/4: H-656Z (3)

17-2023 M8 MODELS (EXCEPT: 2023 FLHXSE & FLTRXSE)

Backing Plate: 81-015-1C

Breather Bolts: 18-457-4C

Breather Bolt Copper Washers: H-070 (2)

Breather Bolt O-Rings (2pack): H-024

Throttle Body Gasket: 18-457-3

Throttle Body Hardware, 1/4-20 x 3/4: H-656Z (3)

M8 Throttle Body Badge: 18-203-8

M8 Servo Cover: 81-016-1B

Stainless Steel Washers: H-338S(3)

6-32 X ¼ Sockethead: H-507Z (3)

ELBOW & FILTER ASSEMBLY

Intake Elbow: 81-000-2C

Filter Base Cover: 81-000-5B

3M Tape 94 Primer: H-087

O-Ring - Bracket to Elbow: H-072

Intake Elbow Socket Bolts: H-654Z (3)

 Monster Performance Air Filter: 81-000-3

Beveled Outer Filter Cover, Chrome: 81-105-1C

Rear Outer Filter Cover, Chrome: 81-100-2C

00-17 TWIN CAM (EXCEPT: FBW) 

• 2001-2017 Twin Cam Delphi EFI (Fuel Injected)
• 1999-2006 Twin Cam CV Carb
• *NOTE: Will not fit Fly-By-Wire Models: 08-17 FLT Touring  / 16-17 Softail / 16-17 Dyna FXDLS & 99-01 F.I. FLT 

 08-16 TOURING / 16-17 SOFTAIL  (FBW)

• 2008-2016 FLT Touring / Bagger - FLHT / FLHR / FLHX / FLTR / H-D FL Trike 
• 2016-2017 Softails 
• 2016-2017 Dyna FXDLS 
• 2014-2015 FLSTNSE / 13-14 FXSBSE / 11-12 FLSTSE
• *NOTE: Twin Cam models equipped w/ FBW (Fly-by-Wire or Throttle-by-Wire) 

 91-UP XL SPORTSTER 

• 1991-up Sportster 883 / 1200  with CV Carb or Delphi EFI 

17-2023 M8 MODELS (EXCEPT: 2023 FLHXSE & FLTRXSE)

• 2017-up FLT Touring / Bagger - FLHT / FLHR / FLHX / FLTR 
• 2018-up Softail Models 

FITMENT DISCLAIMER

Fitment information is provided as a general reference only and is not guaranteed for any motorcycle, whether stock or modified. Compatibility may vary by year, model, and individual configuration.

Customers are responsible for verifying fitment prior to purchase. House of Harley-Davidson assumes no liability for purchases made based on incorrect or unverified fitment information.

Please contact our Parts Department with any questions before ordering at 414-282-2211