Yamaha XT660R S Service Manual

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CHAS
FRONT WHEEL AND BRAKE DISC
EAS00527
CHECKING THE FRONT BRAKE DISC
1. Check:
• brake disc
Damage/galling
→
Replace.
2. Measure:
• brake disc deflection
Out of specification
→
Correct the brake
disc deflection or replace the brake disc.
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a. Place the motorcycle on a suitable stand so
that the front wheel is elevated.
b. Before measuring the front brake disc
deflection, turn the handlebar to the left or
right to ensure that the front wheel is sta-
tionary.
c. Remove the brake caliper.
d. Hold the dial gauge at a right angle against
the brake disc surface.
e. Measure the deflection 3.0 mm (0.12 in)
below the edge of the brake disc.
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Brake disc deflection limit (maxi-
mum)
0.15 mm (0.006 in)
3. Measure:
• brake disc thickness
Measure the brake disc thickness at a few
different locations.
Out of specification
→
Replace.
Brake disc thickness limit (mini-
mum)
4.0 mm (0.16 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