Yamaha XT660R S Service Manual

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ENG
ROCKER ARMS AND CAMSHAFT
EAS00206
CHECKING THE ROCKER ARMS AND
ROCKER ARM SHAFTS
The following procedure applies to both of the
rocker arms and rocker arm shafts.
1. Check:
• rocker arm
Damage/wear
→
Replace.
2. Check:
• rocker arm shaft
Blue discoloration/excessive wear/pitting/
scratches
→
Replace or check the lubrica-
tion system.
3. Measure:
• rocker arm inside diameter
Out of specification
→
Replace.
Rocker arm inside diameter
12.000 ~ 12.018 mm
(0.4724 ~ 0.4731 in)
<Limit>: 12.036 mm (0.4739 in)
4. Measure:
• rocker arm shaft outside diameter
Out of specification
→
Replace.
Rocker arm shaft outside diame-
ter
11.981 ~ 11.991 mm
(0.4717 ~ 0.4721 in)
<Limit>: 11.955 mm (0.4707 in)

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