If you have the extra time and funds looking into a full tune up and valve adjustment. Periodic Maintenance Chart, Air Filter Servicing, Brake Fluid, Brake Inspection, Brake Pads, Clutch Cable Adjustment, Drive Chain Adjustment, Engine Idle Speed. Turn the idle adjustment screw clockwise or counterclockwise until the engine idles at. Make / Model Specific. Yamaha Motorcycles. TTR. TTR-125L chain adjusting.