23
7. Carburetor Service Guide
Rich Down Adjustment
1. Turn the idling limiter (L-needle) clockwise (CW) to
the position of maximum engine speed. (Peak)
2. Turn the throttle valve adjust screw in either
direction to match to the regulated ID peak speed.
(Refer to page 15 "5. Carburetor Specifications- ID
Peak Engine Speed".)
3. Turn the L-needle counterclockwise (CCW) and
execute the rich down adjustment.
(Refer to page 15 "5. Carburetor Specifications- ID
Rich Down".)
4. Turn the throttle valve adjust screw in either
direction and set the ID speed.
(Refer to page 15 "5. Carburetor Specifications-
Set ID Engine Speed".)
5. Check that rotational speed accelerates normally
between idling state and full throttle within the
regulated number of revolutions.
(Refer to page 15 "5. Carburetor Specifications-
Standard Engine Speed".)
.
Confirmation after adjustment
●
For some models: After adjustment is completed,
be sure to install the new limiter cap.
(Refer to page 18 "7-3 Limiter Cap Removal/
Installation".)
●
Be sure to reattach the dust cover.
If the engine is run while the throttle valve's
dust cover is removed, dust or alien matter
may adhere to the throttle valve's rear
contoured or the plunger contacting surfaces.
If they become worn, the L-needle will fall
causing engine start failure.
Caution:
Rich Down:
Adjust the idle needle to a slightly richer mixture in order to
maintain a stable idling speed and get a good acceleration.
Peak engine speed
Set engine speed
Peak
Rich Down
Best
C
onsum
pt
ion
(
ℓ
/h)
(rpm)
Throttle Valve
Adjust Screw
L-needle
Dust Cover
Limiter Cap
Summary of Contents for CHTZ2401
Page 31: ...1001 SY NZ003...
