Yamaha YFM350BAT, Owner'S Manual

Page: 129 / 173

8-25
EBU00296
Carburetor adjustment
The carburetor is a vital part of the engine and
requires very sophisticated adjustment. Most
adjusting should be left to a Yamaha dealer
who has the professional knowledge and ex-
perience to do so. However, the idling speed
may be performed by the owner as a part of
the usual maintenance routine.
CAUTION:
The carburetor was set at the Yamaha fac-
tory after many tests. If the settings are
disturbed by someone without sufficient
technical knowledge, poor engine perfor-
mance and damage may result.
EBU13020
Idle speed adjustment
NOTE:
_
A diagnostic tachometer must be used for this
procedure.
_
1. Start the engine and warm it up for a few
minutes at approximately 1,000 to
2,000 r/min. Occasionally rev the engine
to 4,000 to 5,000 r/min. The engine is
warm when it quickly responds to the
throttle.
2. Connect the tachometer to the spark plug
lead, and then set the idle to the specified
idling speed by adjusting the throttle stop
screw. Turn the screw in direction
a
to
increase the engine speed, and in direc-
tion
b
to decrease the engine speed.
Specified idle speed:
1,450–1,550 r/min
U5WH11.book Page 25 Monday, March 29, 2004 3:21 PM