Moroso Air/Oil Separator - Twin CAM W/S&s Teardrop AIR Cleaner POL — Harley-Davidson (1999-2017)

Moroso air-oil separator for Twin Cam engines with S&S Teardrop air cleaner, designed to intercept crankcase vapors, oil mist, and moisture before they enter the intake system. Keeps the breather system functional while protecting your air filter, throttle body, intake valves, and pistons from excessive oil and carbon buildup.

Features

• Filters crankcase vapors, unburned fuel, oil mist, and moisture from breather system
• Two-piece body design unscrews for easy cleaning and service
• Does not vent to atmosphere—captures oil in the canister to keep your bike and the ground clean
• Reduces detonation and knock caused by contaminated intake charge
• Made in the U.S.A.

Specifications

• Brand: Moroso
• Manufacturer Part #: 85719
• UPC: 84663857195
• Length: 9 in
• Width: 6 in
• Height: 5 in
• Weight: 2 lbs

Fitment

Fits Harley-Davidson Twin Cam engines equipped with an S&S Teardrop air cleaner.

Frequently Asked Questions

Why is this better than venting to atmosphere?

Atmospheric vents dump oil onto your bike and the ground. Moroso's sealed design captures oil in the canister for mess-free operation and environmental compliance.

How often do I need to clean it?

Service intervals depend on riding conditions. The two-piece design unscrews easily for inspection and cleaning whenever oil accumulation is visible.

Will this reduce performance?

No. By keeping clean air entering the engine, the separator prevents detonation and knock while improving combustion quality and valve life.

Does this work with stock breather hoses?

It plumbs inline with your factory breather system. Confirm hose routing with Moroso if your bike has aftermarket intake modifications.

What's included?

The two-piece air-oil separator body with mounting hardware. Hoses and fittings vary by application—verify fitment before ordering.