Page 24 of 142
3-1
3
EBU17680
DESCRIPTION
EBU17690Left view
EBU17700Right view
1. Front shock absorber assembly
2. Spark plug
3. Fuel cock
4. Starter (choke)
5. Throttle stop screw
6. Rear shock absorber assembly
7. Owner’s tool kit
8. Engine oil drain bolt
9. Shift pedal
345
6
7
2
1
9
8
1. Spark arrester
2. Fuse
3. Battery
4. Air filter case
5. Rear brake fluid reservoir
6. Fuel tank cap
7. Oil filter element
8. Engine oil filler cap
9. Brake pedal
10.Rear brake light switch
8 146
5
2,3
7
9
10
U1BT61E0.book Page 1 Tuesday, April 6, 2010 1:28 PM
Page 35 of 142

4-10
4 doctor immediately. If gasoline spills on your
skin, wash with soap and water. If gasoline
spills on your clothing, change your clothes.
NOTICEECB00070Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system.Your Yamaha engine has been designed to use
regular unleaded gasoline with a research octane
number of 91 or higher. If knocking (or pinging) oc-
curs, use a gasoline of a different brand. Use of un-
leaded fuel will extend spark plug life and reduce
maintenance costs.EBU18820Fuel cock The fuel cock supplies fuel from the tank to the car-
buretor while also filtering it.
The fuel cock lever positions are explained as fol-
lows and shown in the illustrations.OFF
With the fuel cock lever in this position, fuel will not
flow. Always turn the fuel cock lever to this position
when the engine is not running.
1. Arrow mark positioned over “OFF”
OFF1
U1BT61E0.book Page 10 Tuesday, April 6, 2010 1:28 PM
Page 135 of 142

10-2
10
Type:
SAE 5W-30, 10W-30, 10W-40, 15W-40, 20W-40 or 20W-
50
Recommended engine oil grade:
API service SG type or higher, JASO standard MA
Engine oil quantity:
Without oil filter element replacement:
1.25 L (1.32 US qt, 1.10 Imp.qt)
With oil filter element replacement:
1.35 L (1.43 US qt, 1.19 Imp.qt)Air filter:Air filter element:
Wet element
Fuel:Recommended fuel:
YFM250RA Unleaded gasoline only
YFM250RSEA Unleaded gasoline only
YFM25RA Regular unleaded gasoline only
YFM25RSEA Regular unleaded gasoline only
Fuel tank capacity:
9.0 L (2.38 US gal, 1.98 Imp.gal)
Fuel reserve amount:
1.0 L (0.26 US gal, 0.22 Imp.gal)Carburetor:Type × quantity:
BSR29 x 1Spark plug (s):Manufacturer/model:
NGK/DR7EA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:
Wet, multiple-disc
Operation:
Left hand operationTransmission:Primary reduction system:
Spur gear
Primary reduction ratio:
76/22 (3.455)
Secondary reduction system:
Chain drive
0 10 30 50 70 90 110 130 ˚F
–20 –10 0 10 20 30 40 50 ˚CSAE 5W-30
SAE 10W-30
SAE 10W-40
SAE 15W-40
SAE 20W-40SAE 20W-50
U1BT61E0.book Page 2 Tuesday, April 6, 2010 1:28 PM
Page 140 of 142

INDEX
AAccessories and loading ................................................ 6-6
Air filter element, cleaning ............................................ 8-14BBattery .......................................................................... 8-35
Brake and clutch levers, checking and lubricating ....... 8-32
Brake fluid, changing .................................................... 8-25
Brake fluid level, checking ............................................ 8-23
Brake lever free play, checking the front ...................... 8-25
Brake lever (YFM25RA/YFM250RA) ............................. 4-5
Brake lever (YFM25RSEA/YFM250RSEA) .................... 4-5
Brake light switches ..................................................... 8-27
Brake pads, checking the front and rear ...................... 8-22
Brake pedal .................................................................... 4-6
Brake pedal, checking and lubricating ......................... 8-33
Brake pedal position, checking .................................... 8-25
Brakes .......................................................................... 8-22
Brakes, front and rear .................................................... 5-3CCables, checking and lubricating ................................. 8-31
Carburetor, adjusting .................................................... 8-20
Chassis fasteners ........................................................... 5-6
Cleaning ......................................................................... 9-1
Clutch lever .................................................................... 4-4
Clutch lever free play, adjusting ................................... 8-28DDrive chain ..................................................................... 5-4
Drive chain, lubricating ................................................. 8-31Drive chain slack .......................................................... 8-29
EEngine break-in .............................................................. 6-4
Engine, cold start ........................................................... 6-1
Engine idling speed ...................................................... 8-20
Engine oil ....................................................................... 5-3
Engine oil and oil filter element .................................... 8-11
Engine, starting a warm ................................................. 6-2
Engine stop switch ......................................................... 4-2FFuel ......................................................................... 4-8, 5-3
Fuel cock ...................................................................... 4-10
Fuel tank cap .................................................................. 4-8
Fuse, replacing ............................................................. 8-38HHandlebar switches ........................................................ 4-2
Headlight beam, adjusting ............................................ 8-41
Headlight bulb, replacing .............................................. 8-39IIdentification numbers .................................................. 11-1
Indicator light .................................................................. 4-2
Instruments, lights and switches .................................... 5-6LLabel locations ............................................................... 1-1
Light switch .................................................................... 4-3MMain switch .................................................................... 4-1
Maintenance and lubrication chart ................................. 8-5
U1BT61E0.book Page 1 Tuesday, April 6, 2010 1:28 PM