check engine YAMAHA BIG BEAR PRO 400 2004 User Guide

8-45
9. Apply all-purpose grease to the air filter ele-
ment seat.
10. Install the air filter element on the frame.
11. Install the air filter element.
12. Install the air filter case cover by installing the
screws.
13. Install the seat.NOTE:_ The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the machine is operated in extremely dusty
areas. Each time air filter element maintenance is
performed, check the air inlet to the air filter case
for obstructions. Check the air filter element rubber
joint to the carburetor and manifold fittings for an
airtight seal. Tighten all fittings securely to avoid
the possibility of unfiltered air entering the engine. _
U4SH6B.book Page 45 Tuesday, May 27, 2003 4:39 PM

8-55 1. Adjusting bolt 2. Locknut
a. Throttle lever free play
1. Boulon de réglage 2. Contre-écrou
a. Jeu du levier d’accélération
1. Perno de ajuste 2. Contratuerca
a. Juego libre de la palanca del acelerador
1. Brake pad a. Wear limit
1. Plaquette de frein a. Limite d’usure
1. Pastillas del freno a. Límite de desgaste
EBU00307
Throttle lever adjustmentNOTE:Adjust the engine idling speed before adjusting the
throttle lever free play.1. Loosen the locknut.
2. Turn the adjusting bolt until the throttle lever
free play is 3.0–5.0 mm.
3. Tighten the locknut.
EBU13770
Front brake pad check
Check the brake pads for damage and wear. If a
brake pad thickness is less than 1 mm, have a
Yamaha dealer replace the pads as a set.NOTE:_ The wheels need to be removed to check the
brake pads. (See page 8-79 for removal and in-
stallation procedures.) _
U4SH6B.book Page 55 Tuesday, May 27, 2003 4:39 PM

8-99
EBU00440Troubleshooting chart1. Fuel
Check if there is fuel
in the fuel tank.There is fuel.Turn the fuel cock
lever to “OFF”.No fuel.Fuel cock is
clogged.
Clean the
fuel cock. Some fuel.Turn the fuel cock
lever to “RES”.Restart the engine.
No fuel.Supply fuel.
2. Compression
Use the electric
starter to see if
there is compression.There is compression.
Compression normal.
No compression.Ask a Yamaha dealer to
inspect.
3. Ignition
Remove the
spark plug and
check electrodes.WetWipe clean with dry cloth.
DryAttach spark plug cap and
ground to chassis.Use the
electric starter.Spark is good.Ignition system is
normal.
Spark is weak.
Adjust the spark plug gap
or replace the spark plug. No spark.
Ask a Yamaha dealer to
inspect. 4. Battery
Use the electric starter.Engine turns over
quickly.Battery is good.
Engine turns over
slowly.Check the connections.Check the
fuel flow.
Turn the fuel cock
lever to “ON”.
Remove the fuel hose
from the fuel cock.
U4SH6B.book Page 99 Tuesday, May 27, 2003 4:39 PM