Adjusting The Carburetor; Adjusting The Engine Idling; Speed - Yamaha Star XV250G 2015 Owner's Manual

Periodic maintenance and adjustment
case. The engine should never
be operated without the air filter
element installed, otherwise the
piston(s) and/or cylinder(s) may
become excessively
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9. Install the air filter case cover by
installing the screws.
10. Connect the hoses to the air filter
case.
11. Push the air filter case onto the air
filter case joint, and then tighten
the clamp screw.
12. Install the bolts.
7

Adjusting the carburetor

The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
worn.
carburetor adjustments should be left
to a Yamaha dealer, who has the nec-
essary professional knowledge and ex-
perience. The adjustment described in
the following section, however, may be
serviced by the owner as part of rou-
tine maintenance.
NOTICE
The carburetor has been set and ex-
tensively tested at the Yamaha fac-
tory. Changing
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
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Adjusting the engine idling

speed

The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
The engine should be warm before
making this adjustment.
TIP
 The engine is warm when it quick-
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 A diagnostic tachometer is need-
these settings
1. Attach the tachometer to the
2. Check the engine idling speed
7-14
ly responds to the throttle.
ed to make this adjustment.
spark plug lead.
and, if necessary, adjust it to
specification by turning the throt-
tle stop screw. To increase the en-
gine idling speed, turn the screw in
direction (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
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