Jet -GURTNER-

The main nozzle is significantly involved in the mixture preparation of the carburettor. If it is too small, the engine dies under full load and/or runs so lean that the piston and cylinder overheat and cylinder damage would result. If, on the other hand, it is too large, the mixture is overgreased, the engine runs very unevenly and can only deliver a fraction of its possible power. The ideal compromise must be found here.

To determine the correct main nozzle, it is first chosen from the belly so large that the target should be an engine stuttering strongly under full load. Of course it needs some experience, but a nozzle can also be changed quickly. If one found such a nozzle one mounts now as long as a smaller nozzle until the engine does not stutter under full load any more. Thus one already has an ideal basic nozzle which ensures that the engine does not receive too little fuel under full load, which it also needs to cool the piston and cylinder. A safety optimum is a motor adjusted in this way, which throttles very slightly briefly when the throttle is closed again under full load.

Gurtner, a French manufacturer of carburettors with more than 100 years of tradition, is very popular with French scooter manufacturers as an original equipment manufacturer. Almost all 50cc Peugeot automatic scooters contain the proven Gurtner carburettors. Tip: The Peugeot vehicles are often very lean tuned, an enlargement of the main nozzle lets the vehicles accelerate mostly clearly more harmoniously with a better power development under load.

(machine-translated)