Page 122 of 452
4-51
CAUTION:_ Never turn an adjusting mechanism beyond
the minimum and maximum settings. _
WARNING
_ Suspension components become hot during
operation. Never touch the compression
damping force adjusting screw, the rebound
damping force adjusting screw or the oil reser-
voir with your bare hand or skin until suspen-
sion components have cooled. _ 
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        Page 410 of 452
8-143
EBU04130
Troubleshooting
Although Yamaha machines receive a rigid in-
spection before shipment from the factory, trouble
may occur during operation. 
Any problem in the fuel, compression, or ignition
systems can cause poor starting and loss of pow-
er. The troubleshooting chart describes a quick,
easy procedure for making checks. If your ma-
chine requires any repair, take it to a Yamaha
dealer. 
The skilled technicians at a Yamaha dealership
have the tools, experience, and know-how to prop-
erly service your machine. Use only genuine
Yamaha parts on your machine. Imitation parts
may look like Yamaha parts, but they are often in-
ferior. Consequently, they have a shorter service
life and can lead to expensive repair bills.
U5TG61.book  Page 143  Friday, April 2, 2004  11:28 AM 
     
        
        Page 430 of 452
10-1
EBU04280
1-SPECIFICATIONS 
MODEL YFZ450
Dimension:
Overall length
Overall width
Overall height
Seat height
Wheel base
Ground clearance
Minimum turning radius1,840 mm
1,170 mm 
1,090 mm 
800 mm 
1,280 mm 
255 mm 
3,500 mm 
Basic weight:
With oil and full fuel tank 169.0 kg
Engine:
Type
Cylinder arrangement
Displacement
Bore 
× stroke
Compression ratio
Starting system
Lubrication systemLiquid-cooled, 4-stroke, DOHC
Forward inclined single cylinder
439.0 cm
3
95.0 
× 62.0 mm
11.90 : 1
Electric starter
Dry sump
U5TG61.book  Page 1  Friday, April 2, 2004  11:28 AM