Adjusting The Carburetor; Adjusting The Engine Idling Speed - Yamaha Raptor 90 2017 Owner's Manual

3. Tap the spark arrester lightly, and then use a
wire brush to remove any carbon deposits.
4. Insert the spark arrester into the muffler and
align the bolt hole.
5. Install the tailpipe bolt and nut, and then tight-
en the nut to the specified torque.
Tightening torque:
Tailpipe nut:
10 N·m (1.0 kgf·m, 7.2 lb·ft)
EWB02341
WARNING
Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
8
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components.
EBU23941

Adjusting the carburetor

The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the pe-
riodic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. There-
fore, most carburetor adjustments should be left
to a Yamaha dealer, who has the necessary pro-
fessional knowledge and experience. The adjust-
ment described in the following section, however,
may be performed by the owner as part of routine
maintenance.
ECB00481
NOTICE
The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine.
EBU24001

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 lubrica-
tion chart.
TIP
A diagnostic tachometer is needed to make this
adjustment.
1. Start the engine and warm it up.
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