Fuel Control

All models are equipped with feedback carburetors which contain an electronically operated stepper motor. The stepper motor controls the metering pins that vary the size of idle and main air bleed orifices in carburetor body. Stepper motor moves the pins in and out of the orifices by steps, in response to signals received from MCU. The motor has a range of 100 steps, but normal operating area is mid-range.

When the metering pins are "stepped" in direction of orifices, the air/fuel mixture becomes richer. When the pins are "stepped" away from orifices, mixture becomes leaner.