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EBU00413
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.
WARNING
Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe in-
jury or property damage. Make sure there are
no open flames or sparks in the area, including
pilot lights from water heaters or furnaces.
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10-1
EBU00428
SPECIFICATIONS
Model YFM400A
Dimensions:
Overall length 1,984 mm
Overall width 1,085 mm
Overall height 1,120 mm
Seat height 827 mm
Wheelbase 1,233 mm
Ground clearance 245 mm
Minimum turning radius 3,000 mm
Basic weight:
With oil and full fuel tank 250 kg
Noise and vibration level:
Noise level (77/311/EEC) (for Europe) 77.2 dB (A)
Vibration on seat (EN1032, ISO5008) (for Europe) Will not exceed 0.6 m/s
2
Vibration on handlebar (EN1032, ISO5008)
(for Europe)Will not exceed 2.5 m/s
2
Engine:
Engine type Liquid-cooled 4-stroke, SOHC
Cylinder arrangement Forward-inclined single cylinder
Displacement 401 cm
3
Bore
× stroke 84.5
× 71.5 mm
Compression ratio 10.5 :1
Starting system Electric and recoil starter
Lubrication system Wet sump
U5VH61.book Page 1 Friday, May 2, 2003 2:19 PM
