Yamaha YZF-R7 User Manual

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ENG
CONNECTING RODS AND PISTONS
e. Calculate the piston-to-cylinder clear-
ance with the following formula.
f. If out of specification, replace the
crankcases, and the pistons and pis-
ton rings as a set.
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Piston-to-cylinder clearance =
Cylinder bore “C” –
Piston skirt diameter “P”
Piston-to-cylinder clearance
0.028 ~ 0.054 mm
(0.0011 ~ 0.0021 in)
<Limit>: 0.1 mm (0.004 in)
EB404410
CHECKING THE PISTON RINGS
1. Measure:
• piston ring side clearance
Out of specification → Replace the pis-
ton and piston rings as a set.
NOTE:
Before measuring the piston ring side
clearance, eliminate any carbon depos-
its from the piston ring grooves and pis-
ton rings.
Piston ring side clearance
Top ring
0.03 ~ 0.07 mm
(0.0012 ~ 0.0028 in)
<Limit>: 0.12 mm (0.0047 in)
2nd ring
0.02 ~ 0.06 mm
(0.0008 ~ 0.0024 in)
<Limit>: 0.12 mm (0.0047 in)
2. Install:
• piston ring
(into the cylinder)
NOTE:
Level the piston ring in the cylinder with
the piston crown.
a 5 mm (0.20 in)

Yamaha YZF-R7 Specifications

General

Bore x Stroke	80.0mm x 68.6mm
Compression Ratio	11.5:1
Fuel Delivery	Fuel injection
Final Drive	Chain
Front Brakes	Dual 298mm hydraulic disc; ABS
Rear Brakes	245mm hydraulic disc; ABS
Front Tire	120/70ZR17
Rear Tire	180/55ZR17
Wheelbase	54.9 in
Seat Height	32.9 in
Fuel Capacity	3.4 gal
Wet Weight	414 lb
Ground Clearance	5.3 in
Engine Type	Liquid-cooled, 4-stroke, DOHC, 4-valves
Transmission	6-speed
Front Suspension	41mm KYB inverted fork, adjustable preload, rebound and compression damping; 5.1-in travel
Rear Suspension	Single shock, adjustable preload and rebound damping; 5.1-in travel