Mixing ratio of motorcycle carburetor: dilution or concentration?

Carburetor mixture spirals to the right and to the left.

For different motorcycles, the adjustment direction of carburetor mixing ratio screw is different. For horizontal cylinder engines (mostly used for bent beams or old 70, 90 motorcycles) and some old two-stroke vehicles, carburetor mixing is more clockwise than screws to adjust concentration and counterclockwise to adjust dilution.

Vacuum membrane carburetor used for scooters and some straddle-type bicycles, and plunger carburetor used for straddle-type motorcycles above 125, the mixing ratio is thinner when the screw rotates clockwise and thicker when it rotates counterclockwise.

Extended data:

In the multi-functional device of carburetor, the main oil supply device is the basic oil supply structure of carburetor, which is needed by various working conditions of engine except idle speed. Idling device is a device that provides a small but rich mixture at idle speed to maintain the stable minimum speed of the engine. The enrichment device is an additional fuel supply device when the engine is under heavy load to make up for the shortage of main fuel supply.

Throttle is a device that provides extra fuel when the throttle opening suddenly increases when the car accelerates, which makes the engine speed and power increase rapidly. The starting device is a device that provides extremely rich mixture when the engine is cold started. The common method is to install a choke valve in front of the throat to control the air intake.

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