Throttle Valve - BOMBARDIER 1996 Ski-doo MX Z440 Handbook

Pilot jets are numbered from No. 15 (the smallest) to No. 80 (the largest). The number corresponds
to fuel flow and not necessarily to drill size or through-hole diameter. After changing the pilot jet,
check and adjust air screw as described above.
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NOTE : Since the pilot/ air system provides some fuel up to wide open throttle, changes
in this system will affect the throttle valve, jet needle/ needle jet, and main jet metering
systems.

THROTTLE VALVE

PRINCIPLES OF OPERATION
, A01C2VS
1. Throttle Valve
2. 3.0
3. 2.0
The throttle valve is cut away on the air inlet side to help control the fuel/ air mixture at low and
intermediate throttle settings. The size of cutaway also affects acceleration.
Throttle valves are numbered from 0.5 to 4.5 in 0.5 increments based on the size of the cutaway.
The most commonly used configurations are 1.5 to 3.5. The higher the number, the greater the
cutaway and the larger the air flow.
The throttle valve functions in about the same range as the pilot/ air system. After the air screw is
adjusted, it can be used to check the throttle valve selection.
o
NOTE : Too lean of a slide cut-away can cause piston siezures during sudden throttle
closures from large throttle settings.
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