BOMBARDIER 1996 Ski-doo MX Z440 Handbook page 173

, AOICZZS
Example : 6DH7
Basic length of needle.
DH -A single letter would indicate a single taper of the needle, double letter a double taper, and
three letters mean there is a triple taper.
D - Amount of taper at top of needle.
H - Amount of taper at bottom of needle.
Material, type of coating and start of second taper on needle.
o
NOTE : Letter designation of the jet needle indicates the angle of taper. Each letter
(starting with A
F = 1-1/2°, G = 1-3/4°, and H = 2°. This applies to both single and double taper needles.
At the top of the jet needle are five grooves numbered 1 through 5 from top to bottom. The number
3 or middle groove being the starting point for the E-ring. The E-ring position on any jet needle
determines the rich or lean part throttle or mid-range carburetor operation.
Moving E-ring to position 1 or 2 lowers jet needle into needle jet and leans out the fuel/ air mixture.
Similarly, moving E-ring to position 4 or 5 raises jet needle in needle jet and enriches the fuel/ air
mixture.
4
5
Number stamped
here
6
v
0.25° greater than preceding letter. Example: D = 1°, E = 1-1/4°,
Section ENGINE PREPARATION
04
LEAN
2
RICH
04-71