CARBURETTOR CIRCUITS
Pulsar 150/180 DTS-i
Service Station Manual
81
Dealer Development Center
Akurdi Pune
1. Pilot Jet
2. Pilot Outlet Hole
3. Butterfly Valve
4. Volume Control
Screw
5. Idling Adjustment
Screw
Function
Construction
Working
The pilot circuit provides the air fuel mixture at idling when not enough air is being drawn through the
carburettor to cause the main circuit to operate.
The pilot circuit consists of pilot jet, pilot air jet and volume control screw. The pilot jet meters the fuel and
the pilot air jet meters the air quantity. The volume control (VC) screw controls the amount of air fuel mixture
flowing through the pilot outlet.
As the air enters the pilot air inlet the fuel is metered by pilot jet and air quantity is metered by pilot air jet.
The atomized / vaporized mixture is discharged through the pilot outlet. The pilot outlet is located on the
manifold side of the carburettor. Since the throttle valve is almost at fully closed position, air fuel mixture is
supplied mainly by pilot outlet only. Air fuel mixture volume is adjusted by volume control (VC) screw and
mixture becomes lean when volume control (VC) screw turned clockwise and rich when it is turned
Pilot Circuit : Constant Velocity Carburettor
Towards
Engine
Air Inlet
for pilot jet