Yamaha XT660R S Service Manual

9 - 5
TRBL
SHTG
FAULTY FRONT FORK LEGS/
UNSTABLE HANDLING
EAS00861
FAULTY FRONT FORK LEGS
LEAKING OIL
• Bent, damaged or rusty inner tube
• Cracked or damaged outer tube
• Improperly installed oil seal
• Damaged oil seal lip
• Incorrect oil level (high)
• Loose damper rod assembly bolt
• Damaged damper rod assembly bolt copper
washer
• Cracked or damaged cap bolt O-ring
MALFUNCTION
• Bent or damaged inner tube
• Bent or damaged outer tube
• Damaged fork spring
• Worn or damaged outer tube bushing
• Bent or damaged damper rod
• Incorrect oil viscosity
• Incorrect oil level
EAS00864
UNSTABLE HANDLING
Handlebar
• Bent or improperly installed handlebar
Steering head components
• Improperly installed upper bracket
• Improperly installed lower bracket
(improperly tightened ring nut)
• Bent steering stem
• Damaged ball bearing or bearing race
Front fork leg(s)
• Uneven oil levels (both front fork legs)
• Unevenly tensioned fork spring (both front
fork legs)
• Broken fork spring
• Bent or damaged inner tube
• Bent or damaged outer tube
Swingarm
• Worn bearing or bushing
• Bent or damaged swingarm
Rear shock absorber assembly
• Faulty rear shock absorber spring
• Leaking oil or gas
Tire(s)
• Uneven tire pressures (front and rear)
• Incorrect tire pressure
• Uneven tire wear
Wheel(s)
• Incorrect wheel balance
• Broken or loose spoke
• Damaged wheel bearing
• Bent or loose wheel axle
• Excessive wheel runout
Frame
• Bent frame
• Damaged steering head pipe
• Improperly installed bearing race

Yamaha XT660R S Specifications

General

Displacement	660 cc
Bore x Stroke	100.0 mm x 84.0 mm
Compression Ratio	10.0:1
Fuel System	Fuel Injection
Ignition System	TCI
Starter System	Electric
Transmission System	5-speed
Final Drive	Chain
Front Suspension System	Telescopic forks
Front Tyre	90/90-21 M/C 54S
Rear Tyre	130/80-17 M/C 65S
Overall Width	865 mm
Overall Height	1, 230 mm
Seat Height	865 mm
Wheelbase	1, 505 mm
Wet Weight	181 kg
Fuel Tank Capacity	15 litres
Oil Tank Capacity	2.9 litres
Engine Type	Liquid-cooled, 4-stroke, single cylinder, SOHC
Maximum Power	48hp (35kW) @ 6, 000rpm
Frame	Steel diamond
Rear Suspension System	Swingarm, (link suspension)
Front Brake	Single 298mm disc, 2-piston caliper
Rear Brake	Single Disc, 245 mm