2012 YAMAHA YFZ450 fuel

8-31
8
EBU24047Adjusting the throttle lever free play The throttle lever free play should be checked and,
if necessary, adjusted at the intervals specified in
the periodic maintenance and lubrication chart.
The throttle lever free play should measure 2.0–
4.0 mm (0.08 –0.16 in) as shown. Periodically
check the throttle lever free play and, if necessary,
adjust it as follows.TIPThe engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle le-
ver free play.1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle lever free play, turn the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b). 4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24060Valve clearance The valve clearance changes with use, resulting in
improper air-fuel mixture and/or engine noise. To
prevent this from occurring, the valve clearance
must be adjusted by a Yamaha dealer at the inter-
vals specified in the periodic maintenance and lu-
brication chart.1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free play
4
2
1
3
(a)
(b)
U1PD60E0.book Page 31 Monday, June 13, 2011 2:57 PM

8-56
8The following troubleshooting charts represent
quick and easy procedures for checking these vital
systems yourself. However, should your ATV re-
quire any repair, take it to a Yamaha dealer, whose
skilled technicians have the necessary tools, expe-
rience, and know-how to service the ATV properly.
Use only genuine Yamaha replacement parts. Im-
itation parts may look like Yamaha parts, but they
are often inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWB02280Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe inju-
ry or property damage. Make sure there are no
open flames or sparks in the area, including pi-
lot lights from water heaters or furnaces.U1PD60E0.book Page 56 Monday, June 13, 2011 2:57 PM

8-57
8
EBU25784Troubleshooting charts Starting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition. Have a Yamaha dealer
check the ATV.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the ATV.
The engine does not start.
Have a Yamaha dealer
check the ATV.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
U1PD60E0.book Page 57 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