HPi's External Breather system is an add on feature manufactured to fit the HPi V2 and Billet-Pro air cleaner kits. The design helps eliminate oil misting on bike and contamination of intake tract with a fully o-ringed system, billet stainless steel inserts and vacuum tube design. Purpose built to retro fit other select air cleaner kits that use a flat mounting back plate. Allows for a slight misalignment of air cleaner due to head/throttle body fitment issues.

*Please note, not yet available for Sportster® units. Fuel Injected models only.

*Hose Details - 3mm 1/8 ID, High Performance Silicone Vacuum Hose

*M8 Models 2017-2023 Gen I Only, not compatible with 2023.5-'24+ Center-Cooled Models

​ Install Instructions:

​Screw the bolt out of the insert and then pull black spacer off the stainless part and you will see wrench flats for a 9/16 wrench. Install into head with red loc tite, then install the spacer back on the insert with the nipple side towards the head. Install back plate, insert bolt back in, do not use loc tite on that bolt.

Fitment

• Cable Driven 2001-2016 Big Twin/Twin Cam
• Throttle-By-Wire 2008-2016 Big Twins
• 2001-2016 Big Twin/Twin Cam cable-driven applications