Kuryakyn Engine Crankcase Vacuum Manifold

Kuryakyn Engine Crankcase Vacuum Manifolds for Harley-Davidson

Kuryakyn has been a trusted name in the motorcycle aftermarket world since 1989, and their approach to engine breathing components reflects the same attention to detail they bring to every corner of their catalog. When it comes to engine crankcase vacuum manifolds, Kuryakyn targets one of the most overlooked — yet genuinely consequential — aspects of V-Twin engine maintenance: controlling crankcase pressure and preventing oil blow-by from contaminating your air cleaner and intake system.

Why Crankcase Vacuum Management Matters

On Harley-Davidson Twin Cam and Sportster engines, the crankcase breathing system routes oil-laden vapor out of the engine. Without a properly functioning breather or vacuum manifold setup, this vapor condenses and deposits oil directly into the air cleaner, fouling the filter element and creating a messy, performance-robbing situation. Kuryakyn's crankcase vacuum manifold kits are engineered specifically to address this problem, routing excess pressure back into the engine rather than into the intake path.

As the oil-laden air condenses within the breather body, the excess oil is directed back down into the engine rather than into the air cleaner — keeping the intake tract clean and the filter element in serviceable condition for longer. It's a straightforward engineering principle, but one that makes a real-world difference in engine cleanliness and long-term maintenance.

Kuryakyn's Fit-First Engineering Philosophy

What sets Kuryakyn apart in this category is a deep focus on model-specific fitment. Rather than offering generic, one-size-fits-all hardware, their crankcase breather and vacuum manifold solutions are engineered to work with specific Harley-Davidson platforms — from Twin Cam Big Twins covering model years 1993 through 2017, to XL Sportster models. The kits are designed to install between the air cleaner and the carb support bracket, and in many cases reuse stock breather bolts and vent hoses to simplify the installation process and minimize parts count.

This vehicle-specific approach is consistent with Kuryakyn's broader product philosophy. Founded by Tom Rudd — an experienced motorcycle mechanic and pioneer in fuel drag bike racing — the brand was built on the idea that aftermarket parts should fit and perform as well as, or better than, OEM components, while also meeting the standards that discerning V-Twin riders demand. With over three decades of design and manufacturing experience focused on the cruiser and touring motorcycle community, Kuryakyn brings genuine rider knowledge to every product line.

A Performance Upgrade and a Maintenance Solution

Installing a Kuryakyn crankcase vacuum manifold is both a corrective measure and a proactive performance upgrade. By eliminating oil contamination at the air cleaner, riders enjoy cleaner combustion air, a tidier engine bay, and reduced filter maintenance intervals. For Harley-Davidson owners running aftermarket air cleaners — a very common modification — this type of crankcase management hardware is often an essential companion piece that completes the engine breathing system properly.

Browse the full range of engine crankcase vacuum manifold options, or explore everything Kuryakyn has to offer across performance, ergonomics, lighting, and accessories for your motorcycle.