TECHNICAL FEATURES HONDA V45 CARBURETOR CHOKE (BYSTARTER SYSTEM) The engine requires a very rich mixture when it is being cranked. The choke (bystarter) valve opens when the choke lever is operated. As the engine is cranked, a high vacuum develops in the intake tract. This vacuum causes the slow jet to discharge a stream of fuel into the carburetor venturi. CHOKE AIR JET 2 DIAPHRAGM CHOKE VALVE THROTTLE VALVE SLOW JET MAIN AIR JET oil CHOKE CIRCUIT NEEDLE MAIN JET When the throttle valve is opened, vacuum in the manifold now works on the main air jet circuit through the choke circuit. Since, under this condition, no air can get past the main air jet into the main circuit, the quantity discharged is sufficient to produce a rich air-fuel mixture required for starting the engine. Date of Issue: October, 1982 0 HONDA MOTOR CO., LTD. 23-4 352