Yamaha YZF-R6 99 User Manual

4-69
CONNECTING RODS AND PISTONS
ENG
NOTE:
EAS00262
CHECKING THE CYLINDER AND PISTONS
The following procedure applies to all of the cyl-
inders and pistons.
1. Check:
 piston wall
 cylinder wall
Vertical scratches  Replace the crank-
cases, and the piston and piston rings as a
set.
2. Measure:
 piston-to-cylinder clearance
a. Measure cylinder bore “C” with the cylinder
bore gauge.
Measure cylinder bore “C” by taking side-to-
side and front-to-back measurements of the
cylinder. Then, find the average of the measure-
ments.
Cylinder bore gauge
90890-03017
Cylinder bore “C”
65.50  65.51 mm
Max. taper “T” 0.05 mm
Out of round “R” 0.05 mm
b. If out of specification, replace the crank-
cases, and the piston and piston rings as a
set.
c. Measure piston skirt diameter “P” with the
micrometer.
Micrometer
90890-03008
a
4 mm from the bottom edge of the piston
Piston size “P”
Standard 65.460  65.475 mm
d. If out of specification, replace the piston and
piston rings as a set.

Yamaha YZF-R6 99 Specifications

General

Bore x Stroke	65.5 mm x 44.5 mm
Compression Ratio	12.4:1
Ignition	Digital TCI
Transmission	6-speed
Final Drive	Chain
Front Suspension	Telescopic fork
Front Tire	120/60-ZR17
Rear Tire	180/55-ZR17
Seat Height	820 mm
Engine Type	liquid-cooled 4-stroke DOHC 16-valve, inline-4
Rear Suspension	Swingarm
Front Brakes	Dual disc
Rear Brakes	Single disc
Wheelbase	1, 380 mm
Fuel Capacity	17 liters
Dry Weight	169 kg
Length	2, 040 mm
Height	1, 090 mm