Page 41 of 97

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OPERATION AND IMPORTANT RIDING POINTS
EAU16810
Tips for reducing fuel
consumption
Fuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
●Shift up swiftly, and avoid high en-
gine speeds during acceleration.
●Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the en-
gine.
●Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at traf-
fic lights or at railroad crossings).
EAU16841
Engine break-in
There is never a more important peri-
od in the life of your engine than the
period between 0 and 1600 km (1000
mi). For this reason, you should read
the following material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1600 km (1000 mi). The various parts
in the engine wear and polish them-
selves to the correct operating clear-
ances. During this period, prolonged
full-throttle operation or any condition
that might result in engine overheating
must be avoided.
EAU17100
0-1000 km (0-600 mi)
Avoid prolonged operation above
4500 r/min.
1000-1600 km (600-1000 mi)
Avoid prolonged operation above
6000 r/min.
ECA10301CAUTION:
After 1000 km (600 mi) of operation,
the engine oil must be changed and
the oil filter cartridge or element re-
placed.
1600 km (1000 mi) and beyond
The vehicle can now be operated nor-
mally.
5-3
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-41
Engine overheatingEWA10400
WARNING0
●Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
●After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, a\
nd then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the hiss-
ing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
NOTE:
If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended
coolant as soon as possible.
Wait until the
engine has cooled.Check the coolant level
in the reservoir and radiator.
The coolant level is low.
Check the cooling
system for leakage.
The coolant level
is OK.
There is
leakage.
There is no
leakage.
Have a Yamaha dealer check
and repair the cooling system.
Start the engine. If the engine overheats again, have
a Yamaha dealer check and repair the cooling system.
Add coolant. (See NOTE.)
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Page 95 of 97
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INDEX
Tire information .............................6-18
Tire inspection ..............................6-18
Tool kit ................................................6-1
Tripmeter and tachometer modes ......3-6
Troubleshooting ................................6-39 Troubleshooting charts .................6-40
Engine overheating .......................6-41
Turn signal indicator light ...................3-3
Turn signal light bulb, replacing........6-34
Turn signal switch...............................3-9
V Valve clearance ................................6-16
Vehicle identification number .............9-1
W Warning lights ....................................3-3
Wheel bearings, checking ................6-29
Wheels, spoke..................................6-19
XT660Z 07-10 ING 11-03-2008 8:33 Pagina 3