1. When the flow of fuel or air in a carburetor is regulated, this regulation is called "metering."
2. A metering system consists of an air metering device and a fuel metering device.
3. It is not practical to build a carburetor that has only one metering system to regulate the flow of fuel and air from closed throttle to wide open throttle. Therefore, each carburetor has several metering systems to regulate air and fuel flow in different ways at different throttle openings.
4. All OSSA motorcycles, with the exception of the Plonker, use an IRZ double needle carburetor of either 29 mm or 33 mm venturi size. These carburetors all work in the same fashion. However, there are slight differences from one model to another, therefore these differences will be covered in separate sections.
SECTIONS 2 thru 7 WILL COVER THE OPERATION OF THE CARBURETORS FITTED TO ALL 1971 and 1972 OSSA MODELS WITH THE EXCEPTION OF THE PLONKER TRIALS