2012 YAMAHA YFZ450 engine

8-58
8Engine overheating
WARNING
EWB02290Wait for the engine and radiator to cool before removing the radiator cap. You could be burned by
hot fluid and steam blown out under pressure. Always put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the rec-
ommended coolant as soon as possible.Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer check
and repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
U1PD60E0.book Page 58 Monday, June 13, 2011 2:57 PM

9-1
9
EBU25860
CLEANING AND STORAGE
EBU25902Cleaning Frequent, thorough cleaning of your ATV will not
only enhance its appearance but will improve its
general performance and extend the useful life of
many components.1. Before cleaning the ATV: a. Block off the end of the exhaust pipe toprevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps are properly installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply de-
greaser to the chain, sprockets or wheel ax-
les.
3. Rinse the dirt and degreaser off with a garden hose. Use only enough pressure to do the job.
WARNING! Wet brakes may have reduced stopping ability, increasing the chance of
an accident. Test the brakes after washing.
Apply the brakes several times at slow
speeds to let friction dry out the linings.
[EWB02311]
NOTICE: Excessive water pressure may cause water seepage and deteriora-
tion of wheel bearings, brakes, transmis-
sion seals and electrical devices. Many
expensive repair bills have resulted from
improper high-pressure detergent applica-
tions such as those available in coin-oper-
ated car washers.
[ECB00711]
4. Once most of the dirt has been hosed off,
wash all surfaces with warm water and mild,
detergent-type soap. An old toothbrush or bot-
tle brush is handy for hard-to-reach places.
5. Rinse the ATV off immediately with clean wa- ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Dry the chain and lubricate it to prevent it from rusting.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
8. Automotive type wax may be applied to all painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
abrasives which may mar the paint or protec-
tive finish. When finished cleaning, start the
engine and let it idle for several minutes.
U1PD60E0.book Page 1 Monday, June 13, 2011 2:57 PM

9-2
9
EBU25933Storage Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover. NOTICE: Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.
[ECB00721]
Long-term
Before storing your ATV for several months: 1. Follow all the instructions in the “ Cleaning”
section of this chapter.
2. Turn the fuel cock lever to “OFF ”.
3. Drain the carburetor float chamber by loosen- ing the drain bolt; this will prevent fuel deposits
from building up. Pour the drained fuel into the
fuel tank.
4. Fill up the fuel tank and add fuel stabilizer (if available) to prevent the fuel from deteriorat-
ing. 5. Perform the following steps to protect the cyl-
inder, piston rings, etc. from corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place the spark plug on the
cylinder head so that the electrodes are
grounded. (This will limit sparking during
the next step.)
d. Turn the engine over several times with the starter. (This will coat the cylinder wall with
oil.)
e. Remove the spark plug cap from the spark plug, and then install the spark plug and
the spark plug cap.
6. Lubricate all control cables and the pivoting points of all levers and pedals.
7. Check and, if necessary, correct the tire air pressure, and then block up the ATV so that
all of its wheels are off the ground. Alternative-
Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1
oz of stabilizer to each gallon of fuel)U1PD60E0.book Page 2 Monday, June 13, 2011 2:57 PM

10-1
10
EBU25961
SPECIFICATIONS
Dimensions:Overall length:1840 mm (72.4 in)
Overall width: 1170 mm (46.1 in)
Overall height:
1090 mm (42.9 in)
Seat height: 810 mm (31.9 in)
Wheelbase: 1280 mm (50.4 in)
Ground clearance:
255 mm (10.0 in)
Minimum turning radius: 3500 mm (138 in)Weight:With oil and fuel:
169.0 kg (373 lb)Noise and vibration level:Noise level (77/311/EEC):82.0 dB(A)@3750 r/min (EUR)(FRA)(GBR)
A-weighted sound power level:
98.0 dB(A)@3750 r/min (EUR)(FRA)(GBR)
Vibration on seat (EN1032, ISO5008): Will not exceed 0.5 m/s ² (EUR)(FRA)(GBR)
Vibration on handlebar (EN1032, ISO5008): Will not exceed 2.5 m/s ² (EUR)(FRA)(GBR)
Engine:Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement: Forward-inclined single cylinder
Displacement:
449 cm ³
Bore × stroke:
95.0 × 63.4 mm (3.74 × 2.50 in)
Compression ratio: 11.40 : 1
Starting system:
Electric starter
Lubrication system: Dry sumpEngine oil:Recommended brand:
YAMALUBE
U1PD60E0.book Page 1 Monday, June 13, 2011 2:57 PM

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:1.75 L (1.85 US qt, 1.54 Imp.qt)
Quantity in oil tank:
1.55 L (1.64 US qt, 1.36 Imp.qt)
Quantity in crankcase: 0.20 L (0.21 US qt, 0.18 Imp.qt)
With oil filter element replacement: 1.85 L (1.96 US qt, 1.63 Imp.qt)
Quantity in oil tank:
1.55 L (1.64 US qt, 1.36 Imp.qt)
Quantity in crankcase: 0.30 L (0.32 US qt, 0.26 Imp.qt)
Cooling system:Coolant reservoir capacity (up to the maximum level mark):0.29 L (0.31 US qt, 0.26 Imp.qt)
Radiator capacity (including all routes):
1.30 L (1.37 US qt, 1.14 Imp.qt)Air filter:Air filter element:Wet elementFuel:Recommended fuel:Premium unleaded gasoline only
Fuel tank capacity: 10.0 L (2.64 US gal, 2.20 Imp.gal)
Fuel reserve amount:
1.9 L (0.50 US gal, 0.42 Imp.gal)Carburetor:Type × quantity:
BSR42 x 1Spark plug (s):Manufacturer/model: NGK/CR8E
Spark plug gap: 0.7 –0.8 mm (0.028 –0.031 in)Clutch:Clutch type:
Wet, multiple-discTransmission:Primary reduction system:
Spur gear
Primary reduction ratio: 62/22 (2.818)
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
U1PD60E0.book Page 2 Monday, June 13, 2011 2:57 PM

INDEX
AAccessories and loading ................................................ 6-7
Air filter element, cleaning ............................................ 8-24BBattery .......................................................................... 8-48
Brake and clutch levers, checking and lubricating ....... 8-44
Brake fluid, changing ................................................... 8-36
Brake fluid level, checking ........................................... 8-33
Brake lever ..................................................................... 4-5
Brake lever free play, checking the front ...................... 8-36
Brake light switches ..................................................... 8-38
Brake pads, checking the front and rear ...................... 8-32
Brake pedal .................................................................... 4-6
Brake pedal, checking and lubricating ......................... 8-45
Brake pedal height, checking ....................................... 8-36
Brakes .......................................................................... 8-32
Brakes, front and rear .................................................... 5-4CCables, checking and lubricating ................................. 8-43
Carburetor, adjusting ................................................... 8-30
Chassis fasteners .......................................................... 5-7
Cleaning ......................................................................... 9-1
Clutch lever .................................................................... 4-5
Clutch lever free play, adjusting ................................... 8-39
Coolant .................................................................. 5-4, 8-20
Coolant temperature warning light ................................. 4-2DDrive chain ..................................................................... 5-5Drive chain, lubricating ................................................ 8-43
Drive chain slack .......................................................... 8-41
EEngine break-in .............................................................. 6-5
Engine, cold start ........................................................... 6-1
Engine idling speed ..................................................... 8-30
Engine oil ....................................................................... 5-4
Engine oil and oil filter element .................................... 8-14
Engine, starting a warm ................................................. 6-3
Engine stop switch ......................................................... 4-3FFuel ......................................................................... 4-8, 5-4
Fuel cock ..................................................................... 4-10
Fuel tank cap ................................................................. 4-8
Fuse, replacing ............................................................ 8-50HHandlebar switches ....................................................... 4-3
Headlight beam, adjusting ........................................... 8-53
Headlight bulb, replacing ............................................. 8-51IIdentification numbers .................................................. 11-1
Indicator light and warning light ..................................... 4-2
Instruments, lights and switches .................................... 5-7LLabel locations ............................................................... 1-1
Light switch .................................................................... 4-3MMain switch .................................................................... 4-1
U1PD60E0.book Page 1 Monday, June 13, 2011 2:57 PM