This 1pc Modified Motorcycle Accessories CV40 CVK34 36 40mm Carburetor Original Modified Mixing Ratio Adjustment Screw is designed to fine-tune the fuel-air mixture ratio in carburetors for optimal engine performance. Compatible with CV40 and CVK34 carburetors with 36mm and 40mm bore sizes, this adjustment screw allows riders to customize their fuel-air mixture to suit different riding conditions and engine setups. Whether it's for fine-tuning engine performance or accommodating modifications, this adjustment screw provides riders with greater control over their motorcycle's fuel delivery, enhancing overall performance and efficiency.