wheel YAMAHA YFM350R 2003 User Guide

7-39
TURNING YOUR ATV
To achieve maximum traction while riding off-road,
the two rear wheels are mounted solidly on one
axle and turn together at the same speed. There-
fore, unless the wheel on the inside of the turn is
allowed to slip or lose some traction, the ATV will
resist turning. A special turning technique must be
used to allow the ATV to make turns quickly and
easily. It is essential that this skill be learned first at
low speed.
WARNING
_ Always follow proper procedures for turning
as described in this Owner’s Manual. Practice
turning at low speeds before attempting to turn
at faster speeds. Do not turn at speeds too fast
for your skills or the conditions. _
U5NF62.book Page 39 Wednesday, May 8, 2002 1:40 PM

7-41 1. Lean towards inside of turn.
2. Support your weight on the outer footboard.
1. Se pencher vers l’intérieur du virage.
2. Faire reposer son poids sur le repose-pied externe.
1. Inclínese hacia el interior del giro.
2. Descanse su peso en el descansapie externo.
As you approach a curve, slow down and begin to
turn the handlebars in the desired direction. As
you do so, put your weight on the footboard to the
outside of the turn (opposite your desired direc-
tion) and lean your upper body into the turn. Use
the throttle to maintain an even speed through the
turn. This maneuver will let the wheel on the inside
of the turn slip slightly, allowing the ATV to make
the turn properly.
This procedure should be practiced at slow speed
many times in a large off-road area with no obsta-
cles. If an incorrect technique is used, your ATV
may continue to go straight. If the ATV doesn’t
turn, come to a stop and then practice the proce-
dure again. If the riding surface is slippery or loose,
it may help to position more of your weight over the
front wheels by moving forward on the seat. Once
you have learned this technique you should be
able to perform it at higher speeds or in tighter
curves.
U5NF62.book Page 41 Wednesday, May 8, 2002 1:40 PM

7-51
If your ATV has stalled or stopped and you believe
you can continue up the hill, restart carefully to
make sure you do not lift the front wheels which
could cause you to lose control. If you are unable
to continue up the hill, dismount the ATV on the
uphill side. Physically turn the ATV around and
then descend the hill.
If you start to roll backwards, DO NOT use the rear
brake to stop or try to put the ATV in gear. The
ATV could easily tip over backwards. Instead, dis-
mount the ATV immediately on the uphill side.
U5NF62.book Page 51 Wednesday, May 8, 2002 1:40 PM

7-59
CROSSING A SLOPE
Traversing a sloping surface on your ATV requires
you to properly position your weight to maintain
proper balance. Be sure that you have learned the
basic riding skills on flat ground before attempting
to cross a sloping surface. Avoid slopes with slip-
pery surfaces or rough terrain that may upset your
balance.
As you travel across a slope, lean your body in the
uphill direction. It may be necessary to correct the
steering when riding on loose surfaces by pointing
the front wheels slightly uphill. When riding on
slopes be sure not to make sharp turns either up or
down hill.
U5NF62.book Page 59 Wednesday, May 8, 2002 1:40 PM

7-69
SLIDING AND SKIDDING
Care should be used when riding on loose or slip-
pery surfaces since the ATV may slide. If unex-
pected and uncorrected, sliding could lead to an
accident.
To reduce the tendency for the front wheels to
slide in loose or slippery conditions, positioning
your weight over the front wheels will sometimes
help.
If the rear wheels of your ATV start to slide side-
ways, control can usually be regained (if there is
room to do so) by steering in the direction of the
slide. Applying the brakes or accelerating is not
recommended until you have corrected the slide.
U5NF62.book Page 69 Wednesday, May 8, 2002 1:40 PM

7-73
WHAT TO DO IF ...
This section is designed to be a reference guide
only. Be sure to read each section on riding tech-
niques completely.
WHAT TO DO ...

If your ATV doesn’t turn when you want it to:
Bring the ATV to a stop and practice the turning
maneuvers again. Be sure you are putting your
weight on the footboard to the outside of the
turn. Position your weight over the front wheels
for better control. (See pages 7-39–7-43.)


If your ATV begins to tip while turning:
Lean more into the turn to regain balance. If nec-
essary, gradually let off the throttle and/or steer to
the outside of the turn. (See pages 7-39–7-43.)


If your ATV starts to slide sideways:
Steer in the direction of the slide if you have the
room. Applying the brakes or accelerating is
not recommended until you have corrected the
slide. (See pages 7-69–7-71.)
U5NF62.book Page 73 Wednesday, May 8, 2002 1:40 PM

8-7
EBU00262
5-PERIODIC MAINTENANCE/LUBRICATION
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
Valves*•Check valve clearance.
•Adjust if necessary.
Spark plug*•Check condition.
•Adjust gap and clean.
•Replace if necessary.Air filter element•Clean.
•Replace if necessary.Every 20–40 hours
(More often in wet or dusty areas.)
Carburetor*•Check idle speed/starter operation.
•Adjust if necessary.Crankcase breather
system*•Check breather hose for cracks or damage.
•Replace if necessary.Exhaust system*•Check for leakage.
•Tighten if necessary.
•Replace gasket(s) if necessary.Fuel line*•Check fuel hose for cracks or damage.
•Replace if necessary.Engine oil•Replace. (Warm engine before draining.)Engine oil filter element•Clean.
•Replace if necessary.Engine oil strainer•Clean.Drive chain•Check and adjust slack/alignment/clean/lube.Brakes*•Check operation/fluid leakage/See NOTE page 8-8.
•Correct if necessary.Clutch*•Check operation.
•Adjust if necessary.Wheels*•Check balance/damage/runout.
•Replace if necessary.U5NF62.book Page 7 Wednesday, May 8, 2002 1:40 PM

8-8 * It is recommended that these items be serviced by a Yamaha dealer.
** Lithium-soap-based grease
NOTE:

Recommended brake fluid: DOT 4


Brake fluid replacement:
1. When disassembling the master cylinders or calipers, replace the brake fluid. Normally check the
brake fluid level and add fluid as required.
2. On the inner parts of the master cylinders and calipers, replace the oil seals every two years.
3. Replace the brake hoses every four years, or if cracked or damaged.
Wheel bearings*•Check bearing assemblies for looseness/damage.
•Replace if damaged.Steering system*•Check operation.
•Repair if damaged.
•Check toe-in.
•Adjust if necessary.Front and rear
suspension*•Check operation.
•Correct if necessary.Upper and lower arm
pivot and steering shaft*•Lubricate every 6 months.**Rear arm pivot*
•Lubricate every 6 months.**Fittings and fasteners*•Check all chassis fittings and fasteners.
•Correct if necessary.Battery*•Check specific gravity.
•Check breather hose for proper routing.
•Correct if necessary.Lights and switches*•Check operation.
•Adjust headlight beam.
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
U5NF62.book Page 8 Wednesday, May 8, 2002 1:40 PM

8-55 1. Locknut 2. Adjusting bolt
1. Contre-écrou 2. Boulon de réglage
1. Contratuerca 2. Perno de ajuste
1. Locknut 2. Adjusting bolt
1. Contre-écrou 2. Boulon de réglage
1. Contratuerca 2. Perno de ajuste
4. Tighten the locknut at the clutch lever.
5. Screw in the adjusting bolt at the rear brake
caliper by hand until it feels tight, then screw it
out 1/8 turn. Tighten the locknut to the speci-
fied torque.CAUTION:_ When tightening the locknut, hold the adjust-
ing bolt with a wrench so that the adjusting
bolt does not turn together with the locknut. _
WARNING
_ Operating with improperly adjusted brakes
could cause the brakes to malfunction, result-
ing in reduced braking performance. This
could increase the chance of a collision or ac-
cident. After adjusting the parking brake, block
the rear of the machine off the ground and spin
the rear wheels. Check to make sure there is
no brake drag. If brake drag is noticed, perform
the adjustment again. _
Tightening torque:
Locknut:
16 Nm (1.6 m·kgf)
U5NF62.book Page 55 Wednesday, May 8, 2002 1:40 PM

8-63 1. Upper wheel hub nut 2. Lower wheel hub nut
1.Écrou supérieur de moyeu de roue
2.Écrou inférieur de moyeu de roue
1. Tuerca superior del cubo de la rueda
2. Tuerca inferior del cubo de la rueda
1. Locknut 2. Adjusting bolt 3. Alignment marks
1. Contre-écrou 2. Boulon de réglage
3. Repères d’alignement
1. Contratuerca 2. Perno de ajuste
3. Marcas de alineación
EBU01194
Drive chain slack adjustment
1. Loosen the rear wheel hub upper and lower
nuts.
2. Loosen the locknuts on each side of the swin-
garm. To tighten the drive chain, turn the ad-
justing bolts in direction
a. To loosen the
drive chain, turn the adjusting bolts in direc-
tion
b and push the wheels forward. Turn
each adjusting bolt exactly the same amount
to maintain correct axle alignment.NOTE:_ There are alignment marks on each side of the
swingarm and on the hub. Use them to check for
proper wheel axle alignment. _3. After adjusting, tighten the locknuts and the
wheel hub nuts to the specified torques.
Tightening torques:
Locknut:
16 Nm (1.6 m·kgf)
Upper wheel hub nut:
120 Nm (12.0 m·kgf)
Lower wheel hub nut:
60 Nm (6.0 m·kgf)
U5NF62.book Page 63 Wednesday, May 8, 2002 1:40 PM