Arlen Ness 18-318

The new Big Sucker™ Stage 1 performance intake for Milwaukee-Eight® (M8) engines adds new features to the original industry leading air cleaner. The new patent-pending hidden breather system is o-ringed at the heads, passes through the backing plate and exits inside the mouth of the throttle body through proprietary shooter tubes

• Increases Horsepower & Torque 
• Eliminates Oil Blow-bye Issues Associated with M8 Engines
• Black Pre-Oiled High Performance Filter 
• Patented backing plate technology (US Patent: US 10,851,741 B1)
• One-Piece Aluminum Backing Plate 
• Aluminum Filter Top Plate Design Eliminates Internal Mounting Hardware 

Aluminum Backing Plate:

• Aluminum Construction 
• Patent-pending hidden breather backing plate technology is a step up from our original patented system. Each breather is o-ringed at the heads, passes through the backing plate and exits inside the mouth of the throttle body through specially formed breather tubes
• Eliminates oil blow-bye  issues associated with performance intakes on M8 engines 
• Patent-pending oil catch is integrated into the backing plate and stops any excess breather oil from reaching the air filter. Oil catch is serviceable, simply bolt-on and off when your ready to wash/service the air filter 
• Formed aluminum filter plate design with integrated mounting studs eliminates any internal mounting hardware 
• Radius air inlet engineered to provide maximum airflow 
• Outer filter lip covers the urethane on the base of the air filter for a clean look 

Performance Air Filter:

• Made from black pre-oiled cotton 
• Engineered for optimum air flow and filtration. Perimeter flow design brings in air from all sides of the filter while filtering out all harmful debris 
• Washable and re-useable, filter service kits are available 

Air Cleaner Cover Options:

• Choose a Arlen Ness® Stage 1 custom cover for an exposed performance look 
• 18-up Softail (FLDE/FLSL/FXLR) single-bolt factory air cleaner covers 

Backing Plate Assembly: 18-393C Chrome / 18-394B Black

• Aluminum Backing Plate, Black
• Aluminum Filter Top Plate
• Filter Top Plate Hardware, Stainless Socket Heads ¼ - 20 x 1-1/2” (2)

Patented Breather Vent System Components: Shooter Tubes & Oil Catch

• Oil Catch: 18-392-3
• Oil Catch Gasket: 18-392-4
• Oil Catch Hardware, Stainless Socket Heads 8-32 x ¾: H-619S (2)
• Shooter / Breather Tube Kit: BT-001

Stage 1 Hardware Kit, M8: HK-18458

• Breather Bolts, Chrome: 18-457-4C (2)
• Throttle Body Gasket: 18-457-3
• Breather Bolt O-Rings: H-024-4 (4)

Logo Plate / Throttle Body Badge Assembly

• Throttle Body Logo Badge: 18-203-8
• Throttle Body Badge, Black Button Heads M6 x 1.0: HM-122B (2)

Additional Components:

• Outer Cover Hardware, Chrome Flat Head 5/16-18 x 5/8: H-525C
• Instruction Sheet: 18392-I

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

• 2017-up FLT Touring / Bagger Models: FLHT / FLHR / FLHX / FLTRX / FLTRU / H-D FL Trike 
• 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