A set of TC Bros breather bolts for all Harley Twin Cam Engines, including crankcase venting.

Two TC Bros Breather Bolts For all Harley Twin Cam Engines - Black and washers on a white background.

TC Bros Breather Bolts For all Harley Twin Cam Engines by TC Bros. aftermarket air cleaners.

Various metal and plastic hardware, including bolts, washers, mesh screens, retaining rings, and gaskets—such as TC Bros. Breather Bolts for Harley-Davidson Twin Cam—are displayed on a white background.

TC Bros. Breather Bolts for Harley-Davidson Twin Cam

$49.95

SKU: 109-0393

Color — Black Anodized

Raw Machined

Black Anodized

Add Carburetor Support Bracket

Required only for carbureted models

In stock
Inventory on the way

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TC Bros. Breather Bolts for Harley-Davidson Twin Cam

Stock airboxes on Harley-Davidson Twin Cams integrate a provision for crankcase breathing through the cylinder heads. Eliminating the airbox to run an aftermarket air cleaner also eliminates the hollow breathing bolts.

Fits all Twin Cam 1999-2017
Available in Raw Machined or Black finish
Permits use of many aftermarket air cleaners (including all TC Bros. units)
Air cleaner support brackets available separately; required for most aftermarket air cleaner installations
Made in USA
CNC-machined from 6061 aluminum

These bolts offer an unobtrusive, alternative crankcase venting option when installing aftermarket air cleaners on your Harley-Davidson. They are CNC-machined from 6061 aluminum and offered in two attractive finishes. Stainless steel vent screens, stainless washers, circlips and foam filter elements are included. Sidestep ugly hoses and bulky breather filters with a set of TC Bros. Breather Bolts. Not legal for sale or use in California.