4-13
4
EBU18992Adjusting the front shock absorber as-
semblies (YFM25RA/YFM250RA)The spring preload can be adjusted to suit the rid-
er’s weight and the riding conditions.
WARNING
EWB00400Always adjust the shock absorber assemblies
on the left and right side to the same setting.
Uneven adjustment can cause poor handling
and loss of stability, which could lead to an ac-
cident.
Adjust the spring preload as follows.
Turn the spring preload adjusting ring in direction
(a) to increase the spring preload and thereby
harden the suspension, and in direction (b) to de-
crease the spring preload and thereby soften the
suspension.TIPA special wrench can be obtained at a Yamaha
dealer to make this adjustment.
1. Projection
2. Seat holder
1
2
1. Spring preload adjusting ring
2. Special wrench
3. Position indicator
1
2
3
4
5
(a)
(b)1
2
3
U1BT61E0.book Page 13 Tuesday, April 6, 2010 1:28 PM
4-14
4
EBU30050Adjusting the front shock absorber as-
semblies (YFM25RSEA/YFM250RSEA)These shock absorber assemblies are equipped
with a spring preload adjusting nut, a rebound
damping force adjusting screw, with a compres-
sion damping force adjusting bolt (for fast com-
pression damping), and a compression damping
force adjusting screw (for slow compression damp-
ing).
WARNING
EWB02491Suspension components become hot during
operation. Never touch the compression
damping force adjusting bolt and screw, the
rebound damping force adjusting screw or
the oil reservoir with your bare hand or skin
until suspension components have cooled.
Always adjust the shock absorber assem-
blies on the left and right side to the same
setting. Uneven adjustment can cause poor
handling and loss of stability, which could
lead to an accident.NOTICEECB00090Never turn an adjusting mechanism beyond
the minimum and maximum settings.TIPAlthough the total number of clicks or turns of a
damping force adjusting mechanism may not ex-
actly match the following specifications due to
small differences in production, the actual number
of clicks or turns always represents the entire ad-
justing range. To obtain a precise adjustment, it
would be advisable to check the number of clicks
or turns of each damping force adjusting mecha-
nism and to modify the specifications as neces-
sary.Spring preload
1. Loosen the locknut. Spring preload setting:
Minimum (soft):
1
Standard:
2
Maximum (hard):
5
U1BT61E0.book Page 14 Tuesday, April 6, 2010 1:28 PM
4-15
42. Turn the spring preload adjusting nut in direc-
tion (a) to increase the spring preload and
thereby harden the suspension, and in direc-
tion (b) to decrease the spring preload and
thereby soften the suspension.
TIPA special wrench can be obtained at a Yamaha
dealer to make this adjustment.The spring preload setting is determined by
measuring distance A, shown in the illustration.
The shorter distance A is, the higher the spring
preload; the longer distance A is, the lower thespring preload. With each complete turn of the
adjusting nut, distance A is changed by 1.5 mm
(0.06 in).1. Spring preload adjusting nut
2. Locknut
3. Special wrench
(a)
(b)1 2
3
Spring preload setting:
Minimum (soft):
Distance A = 209.6 mm (8.25 in)
Standard:
Distance A = 206.0 mm (8.11 in)
Maximum (hard):
Distance A = 197.6 mm (7.78 in)1. Distance A
1
U1BT61E0.book Page 15 Tuesday, April 6, 2010 1:28 PM
4-19
4
NOTICEECB01090Never turn the adjusting mechanism beyond
the minimum and maximum settings.Adjust the spring preload as follows.
1. Loosen the locknut.
2. Turn the spring preload adjusting nut in direc-
tion (a) to increase the spring preload and
thereby harden the suspension, and in direc-
tion (b) to decrease the spring preload and
thereby soften the suspension.
TIPA special wrench can be obtained at a Yamaha
dealer to make this adjustment.The spring preload setting is determined by
measuring distance A, shown in the illustration.
The shorter distance A is, the higher the spring
preload; the longer distance A is, the lower the
spring preload. With each complete turn of the
adjusting nut, distance A is changed by 1.0 mm
(0.04 in).3. Tighten the locknut to the specified torque.
NOTICE: Always tighten the locknut
against the adjusting nut, and then tighten
it to the specified torque.
[ECB00081]
1. Locknut
2. Spring preload adjusting nut
3. Distance A
2
1
(b) 3(a)
Spring preload setting:
Minimum (soft):
Distance A = 234.0 mm (9.21 in)
Standard:
Distance A = 230.0 mm (9.06 in)
Maximum (hard):
Distance A = 222.0 mm (8.74 in)
U1BT61E0.book Page 19 Tuesday, April 6, 2010 1:28 PM
4-20
4
WARNING
EWB00450This shock absorber assembly contains highly
pressurized nitrogen gas. If the shock absorb-
er assembly is damaged, it could explode
causing injury or property damage. Shock ab-
sorber cylinder damage could also result in
poor handling which could cause an accident.Do not tamper with or attempt to open the
cylinder assembly.Do not subject the shock absorber assembly
to an open flame or other high heat.Do not deform or damage the cylinder in any
way.Do not dispose of a damaged or worn out
shock absorber assembly yourself. Take the
shock absorber assembly to a Yamaha deal-
er for any service.
EBU29312Adjusting the rear shock absorber as-
sembly (YFM25RSEA/YFM250RSEA)The spring preload, rebound damping and com-
pression damping forces of the rear shock absorb-
er assembly can be adjusted to suit the rider’s
weight and the riding conditions.
WARNING
EWB02500Suspension components become hot during
operation. Never touch the compression
damping force adjusting screw, the rebound
damping force adjusting dial or the oil reser-
voir with your bare hand or skin until suspen-
sion components have cooled.NOTICEECB00090Never turn an adjusting mechanism beyond
the minimum and maximum settings.Spring preload
1. Loosen the locknut. Tightening torque:
Locknut:
42 Nm (4.2 m·kgf, 30 ft·lbf)
U1BT61E0.book Page 20 Tuesday, April 6, 2010 1:28 PM
4-21
42. Turn the spring preload adjusting nut in direc-
tion (a) to increase the spring preload and
thereby harden the suspension, and in direc-
tion (b) to decrease the spring preload and
thereby soften the suspension.
TIPA special wrench can be obtained at a Yamaha
dealer to make this adjustment.The spring preload setting is determined by
measuring distance A, shown in the illustration.
The shorter distance A is, the higher the spring
preload; the longer distance A is, the lower thespring preload. With each complete turn of the
adjusting nut, distance A is changed by 1.5 mm
(0.06 in).1. Locknut
2. Spring preload adjusting nut
12
(a)
(b)
Spring preload setting:
Minimum (soft):
Distance A = 232.0 mm (9.13 in)
Standard:
Distance A = 228.0 mm (8.98 in)
Maximum (hard):
Distance A = 220.0 mm (8.66 in)1. Distance A
1
U1BT61E0.book Page 21 Tuesday, April 6, 2010 1:28 PM
10-4
10
Rim size:
9 x 8.0ATFront brake:Type:
Dual disc brake
Operation:
Right hand operation
Recommended fluid:
DOT 4Rear brake:Type:
Single disc brake
Operation:
Right foot operation
Recommended fluid:
DOT 4Front suspension:Type:
Double wishbone
Spring/shock absorber type:
YFM250RA Coil spring/oil damper
YFM250RSEA Coil spring/gas-oil damper
YFM25RA Coil spring/oil damper
YFM25RSEA Coil spring/gas-oil damper
Wheel travel:
190 mm (7.5 in)Rear suspension:Type:
Swingarm
Spring/shock absorber type:
Coil spring/gas-oil damperWheel travel:
200 mm (7.9 in)
Electrical system:Ignition system:
DC CDI
Charging system:
AC magnetoBattery:Model:
YTZ7S
Voltage, capacity:
12 V, 6.0 AhHeadlight:Bulb type:
Krypton bulbBulb voltage, wattage × quantity:Headlight:
12 V, 30/30 W × 2
Tail/brake light:
YFM250RA 12 V, 5.0/21.0 W × 1
YFM25RA 12 V, 5.0/21.0 W × 1
Tail/brake light:
YFM250RSEA LED
YFM25RSEA LED
Neutral indicator light:
12 V, 1.7 W × 1Fuse:Fuse:
15.0 A
U1BT61E0.book Page 4 Tuesday, April 6, 2010 1:28 PM
Maintenance chart, emission control system ................. 8-3
Model label ................................................................... 11-2NNeutral indicator light ..................................................... 4-2OOwner’s manual and tool kit ........................................... 8-2PParking ........................................................................... 6-5
Parking brake free play, adjusting ................................ 8-26
Parking brake lever ........................................................ 4-6
Parking on a slope ......................................................... 6-6
Part locations ................................................................. 3-1RRiding your ATV ............................................................. 7-1SSafety information .......................................................... 2-1
Seat .............................................................................. 4-12
Shifting ........................................................................... 6-3
Shift pedal ...................................................................... 4-7
Shift pedal, checking .................................................... 8-33
Shock absorber assemblies, adjusting the front
(YFM25RA/YFM250RA) ............................................ 4-13
Shock absorber assemblies, adjusting the front
(YFM25RSEA/YFM250RSEA) .................................. 4-14
Shock absorber assembly, adjusting the rear
(YFM25RA/YFM250RA) ............................................ 4-18
Shock absorber assembly, adjusting the rear
(YFM25RSEA/YFM250RSEA) .................................. 4-20
Spark arrester, cleaning ............................................... 8-18
Spark plug, checking ...................................................... 8-9
Specifications ............................................................... 10-1
Speed limiter .................................................................. 4-4Starter (choke) ............................................................. 4-11
Start switch .................................................................... 4-3
Steering shaft, lubricating ............................................ 8-35
Storage .......................................................................... 9-2
Suspension, lubricating the upper and lower arm
pivots ......................................................................... 8-34
Swingarm pivots, lubricating ........................................ 8-34
TTail/brake light bulb, replacing
(YFM25RA/YFM250RA) ............................................ 8-41
Tail/brake light (YFM25RSEA/YFM250RSEA) ............ 8-42
Throttle cable free play, adjusting ................................ 8-21
Throttle lever ........................................................... 4-3, 5-3
Tires ............................................................................... 5-4
Troubleshooting ........................................................... 8-43
Troubleshooting chart .................................................. 8-44VValve clearance ........................................................... 8-22
Vehicle identification number ....................................... 11-1WWheel hub bearings, checking ..................................... 8-33
Wheel, installing ........................................................... 8-42
Wheel, removing .......................................................... 8-42
U1BT61E0.book Page 2 Tuesday, April 6, 2010 1:28 PM