On a Harley-Davidson motorcycle, the idle cable and throttle cable serve different purposes and are part of the throttle control system. Here's the difference between the two:
Idle Cable: The idle cable, also known as the idle control cable or idle speed control cable, is responsible for controlling the idle speed of the motorcycle's engine. It connects the idle control lever on the handlebars to the carburetor or throttle body. By adjusting the tension in the idle cable, riders can regulate the engine's idle speed. The idle cable allows the rider to set the desired idle RPM (revolutions per minute) when the throttle is fully released.
Throttle Cable: The throttle cable, also referred to as the throttle control cable or accelerator cable, is responsible for controlling the opening and closing of the throttle valve in the carburetor or the throttle body in fuel-injected models. It connects the throttle grip on the handlebars to the throttle linkage on the carburetor or throttle body. When the rider twists the throttle grip, the throttle cable transfers that motion to the throttle linkage, opening the throttle valve and increasing the engine's RPM, which controls the speed and acceleration of the motorcycle.
In summary, the idle cable is specifically dedicated to controlling the idle speed of the engine, while the throttle cable is responsible for opening and closing the throttle valve, allowing the rider to control the engine's speed and acceleration. Both cables are essential components of the throttle control system, working together to provide the rider with precise control over the motorcycle's engine.