Connecting Rods And Pistons; Removing The Connecting Rods And Pistons; Checking The Cylinder And Piston - Yamaha YZFR1Y(C) 2009 Service Manual

EAS26030
REMOVING THE CONNECTING RODS AND
PISTONS
The following procedure applies to all of the

connecting rods and pistons.

1. Remove:
• Connecting rod cap "1"
• Connecting rod
• Big end bearings
TIP
• Identify the position of each big end bear-
ing so that it can be reinstalled in its origi-
nal place.
• After removing the connecting rods and
connecting rod caps, care should be taken
not to damage the mating surfaces of the
connecting rods and connecting rod caps.
2. Remove:
• Piston pin clips "1"
• Piston pin "2"
• Piston "3"
ECA13810
Do not use a hammer to drive the piston
pin out.
TIP
• For reference during installation, put identifi-
cation marks on the piston crown.
• Before removing the piston pin, deburr the
piston pin clip groove and the piston pin bore
area. If both areas are debarred and the pis-
ton pin is still difficult to remove, remove it
with the piston pin puller set "4".
Piston pin puller set
90890-01304
Piston pin puller
YU-01304
CONNECTING RODS AND PISTONS
3. Remove:
• Top ring
• 2nd ring
• Oil ring
TIP
When removing a piston ring, open the end
gap with your fingers and lift the other side of
the ring over the piston crown.
4. Remove:
• Cylinder
• Cylinder gasket
• Cylinder stud bolts
EAS24390

CHECKING THE CYLINDER AND PISTON

1. Check:
• Piston wall
• Cylinder wall
Vertical scratches → Replace the cylin-
der, and replace the piston and piston
rings as a set.
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