Adjusting The Carburetor; Adjusting The Engine Idling Speed - Yamaha Drag Star XVS125 Owner's Manual

PERIODIC MAINTENANCE AND MINOR REPAIR

Adjusting the carburetor

The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, most
carburetor adjustments should be left
to a Yamaha dealer, who has the
necessary professional knowledge
and experience.
described in the following section,
however, may be serviced by the
owner as part of routine mainte-
nance.
cC
6
The carburetor has been set and
extensively tested at the Yamaha
factory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
EAU00629
Adjusting the engine idling
Carburetor, adjusting
speed
The engine idling speed must be
checked and, if necessary, adjusted
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart.
The adjustment
NOTE:
A diagnostic tachometer is needed to
make this adjustment.
1. Attach the tachometer to the
EC000094
spark plug lead.
2. Start the engine and warm it up
for several minutes at 1,000–
2,000 r/min while occasionally
revving it to 4,000–5,000 r/min.
NOTE:
The engine is warm when it quickly
responds to the throttle.
EAU01168
Engine idling speed
1. Throttle stop screw
NOTE:
If the specified idling speed cannot
be obtained as described above,
have a Yamaha dealer make the
adjustment.
6-14
b
a
1
3. Check the engine idling speed
and, if necessary, adjust it to
specification by turning the throt-
tle stop screw. To increase the
engine idling speed, turn the
screw in direction
decrease the engine idling speed,
turn the screw in direction b.
Engine idling speed:
1,250–1,450 r/min
a.
To