1. The idle speed should be checked and adjusted before and after the carburettors are synchronised (balanced), after checking the valve clearances, and when it is obviously too high or too low. Before adjusting the idle speed turn the handlebars from side-to-side and check the idle speed does not change. If It does, the throttle cables may not be adjusted or routed correctly, or may be worn out. This is a dangerous condition that can cause loss of control of the bike. Be sure to correct this problem before proceeding.
2. The engine should be at normal operating temperature, which is usually reached after 10 to 15 minutes of stop-and-go riding. Place the motorcycle on its sidestand, and make sure the transmission is in neutral.
2.3. Idle speed adjuster (arrowed)
3. The idle speed adjuster is a knurled knob located on the left-hand side of the carburetors (see illustration). With the engine idling, adjust the speed by turning the adjuster until the idle speed listed in this Chapter's Specifications is obtained. Turn the screw clockwise to increase idle speed, and anti-clockwise to decrease it.
4. Snap the throttle open and shut a few times, then recheck the idle speed. If necessary, repeat the adjustment procedure.
5. If a smooth, steady idle can't be achieved, the fuel/air mixture may be incorrect (see Chapter 4) or the carburetors may need synchronising (see Section 17). Also check the intake manifold rubbers for cracks or a loose clamp which will cause an air leak, resulting in a weak mixture.