What is a Banjo Bolt Fitting and How is it Used on a Motorcycle?

A motorcycle’s banjo bolt fitting has nothing to do with the musical instrument, but it is a key part on almost every motorcycle. Here’s what you need to know about a banjo fuel fitting on a motorcycle.

What is a banjo bolt fitting?

A banjo fitting is a special connector used to transfer pressurized fluid, usually from a hydraulic component to a tube or hose. The fitting is comprised of two parts – a spherical union with a threaded end that is drilled to pass fluid, and a special banjo bolt, which is hollow down its length and has a hole drilled in the side, also to pass fluid. The union part, with its round center and threaded end, sort of looks like a banjo, which is how it gets the odd name.

The union is usually attached to the end of a flexible line or hose, such as a brake line, and the bolt secures the union to another component, such as the brake caliper. The bolt is sealed with special washers. The hollow bolt allows fluid to pass from the union, through the bolt, and into the next component.

Where is a banjo fitting used on a motorcycle?

Banjo fittings are seen on almost any motorcycle equipped with hydraulic brakes or a hydraulic clutch. Banjo fittings are typically used in the hydraulic brake system of a motorcycle to connect the flexible brake line to the brake caliper and to the brake master cylinder. You may also see a banjo fitting used to attach oil lines on some motorcycles.

Without a banjo fitting it would be impossible to attach a brake line to the caliper or master cylinder without also turning or twisting the line as its end is threaded into the component.

A banjo fitting is a simple and very clever device that has been around for years but remains essential to the function of almost every motorcycle.

Find banjo bolts and other OEM Service parts for many Harley-Davidson® motorcycle models on H-D.com that can be picked up at you local authorized Harley-Davidson® dealer.

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