Yamaha XT660X Service Manual

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ENG
CYLINDER AND PISTON
EAS00253
REMOVING THE CYLINDER AND PISTON
1. Remove:
• piston pin clips
1
• piston pin
2
• piston
3
CAUTION:
_
Do not use a hammer to drive the piston
pin out.
NOTE:
_
• Before removing the piston pin clip, cover the
crankcase opening with a clean rag to pre-
vent the piston pin clip from falling into the
crankcase.
• Before removing the piston pin, deburr the
piston pin clip’s groove and the piston’s pin
bore area. If both areas are deburred and the
piston pin is still difficult to remove, remove it
with the piston pin puller set
4
.
Piston pin puller set
90890-01304
1
2
3
2. Remove:
• top ring
• 2nd ring
• oil ring
NOTE:
_
When removing a piston ring, open the end
gap with your fingers and lift the other side of
the ring over the piston crown.
EAS00255
CHECKING THE CYLINDER AND PISTON
1. Check:
• piston wall
• cylinder wall
Vertical scratches
→
Replace the cylinder
and the piston and piston rings as a set.

Yamaha XT660X Specifications

General

Displacement	660cc
Bore x Stroke	100.0 mm x 84.0 mm
Compression Ratio	10.0:1
Fuel System	Fuel Injection
Ignition System	TCI
Transmission	5-speed
Final Drive	Chain
Rear Brake	Single disc, Ø 245 mm
Front Tyre	120/70 R17
Rear Tyre	160/60 R17
Maximum Power	48 HP (35.3 kW) @ 6, 000 rpm
Maximum Torque	58.4Nm (43.1lb-ft) @ 5, 250rpm
Front Suspension	Telescopic fork
Rear Suspension	Swingarm, (link suspension)
Fuel Tank Capacity	15 litres
Engine Type	Liquid-cooled, 4-stroke, single cylinder, SOHC, 4-valves