ENGINE
HIGH-PERFORMANCE PISTONS (CONT)
OVER
REPL.
BORE (MM)
DISPL. BORE
SIZES PK KIT
PISTON
REPL. RING CIRCLIPS
REPL. WRIST
TOP-END
FITS MODEL
X STROKE (MM) (CC)
SIZE (MM) (MM) PART #
PART #
SET PART # PART #
PIN PART #
BEARING PART #
YAMAHA 4-STROKE (CONT)
YZ250F 08-11
77
250
77.0
STD
0903-0937 0910-1678
-
CW16
0913-0008
-
13.5:1 Stock Compression
x
79.0
2.0
-
-
3110XG
-
-
-
ArmorGlide skirt coated
53.6
-
-
-
-
-
-
Nikasil Bore
-
-
-
-
-
-
YZ250F 08-11
77
250
77.0
STD
0903-0938 0910-2932
-
CW16
0913-0008
-
14:1 High-Compression
x
-
-
-
-
-
-
ArmorGlide skirt coated
53.6
-
-
-
-
-
-
Nikasil Bore
-
-
-
-
-
-
YZ250F 12-13
77
-
77
STD
0903-1146 -
-
-
-
-
13.5:1 Stock Compression
x
-
-
-
-
-
-
Nikasil bore
53.6
-
-
-
-
-
-
YZ250F 14-15
77
-
77
STD
0903-1143 -
0912-0140
CW16
-
-
YZ250FX 15-16
x
-
-
-
-
-
-
WR250F 15-17
53.6
-
-
-
-
-
-
13.5:1 Stock Compression
-
-
-
-
-
-
Nikasil bore
-
-
-
-
-
-
YZ250F 14-15
77
-
77
-
-
0910-3917
-
CW16
-
-
YZ250FX 15-16
x
-
-
-
-
-
-
WR250F 15-17
53.6
-
-
-
-
-
-
14:1 High Compression
-
-
-
-
-
-
YZ250F 14-15
77
-
77
-
-
0910-3968
-
CW16
-
-
YZ250FX 15-16
x
-
-
-
-
-
-
WR250F 15-17
53.6
-
-
-
-
-
-
Racer’s Choice
-
-
-
-
-
-
14:1 High Compression
-
-
-
-
-
-
TT350 85-98
86
346
86.0
STD
-
0910-2916
3386XC
CW19
-
-
XT350 85-00
x
87
1.0
-
0910-1661
3425XC
-
-
-
9:1 Compression
59.6
1.5
-
0910-2917
-
-
-
-
Cylinder boring and replating required
-
-
-
-
-
-
for oversizes
YZ400F 98-99
92
399
92.0
STD
-
4649M09200 -
CW18
-
-
WR400F 98-00
x
-
-
-
-
-
-
12.5:1 Compression
60.1
-
-
-
-
-
-
-8cc Dome Volume
-
-
-
-
-
-
YZ400F 98-99
92
399
92.0
STD
-
4650M09200 -
CW18
-
-
WR400F 98-00
x
-
-
-
-
-
-
13.5:1 Compression -6.7cc Dome Volume
60.1
-
-
-
-
-
-
YZ426F 00-02
95
426
95.0
STD
-
4693M09500 -
CW19
-
-
WR426F 01-02
x
97.0
2.00
-
0910-2918
-
-
-
-
12.5:1 Stock Compression
60.1
-
-
-
-
-
-
YZ426F 00-02
95
426
95.0
STD
-
0910-2919
-
CW19
-
-
WR426F 01-02
x
97.0
2.00
-
0910-2920
-
-
-
-
13.5:1 High Compression
60.1
-
-
-
-
-
-
YZ450F 03-05
95
449
95.0
STD
0903-0563 0910-0373
-
CW18
-
-
WR450F 03-06
x
97.0
2.00
-
0910-0374
-
-
-
-
12.5:1 Standard Compression.
63
-
-
-
-
-
-
Nikasil Bore-Cylinder
sleeving or replating required for oversizes
-
-
-
-
-
-
YZ450F 03-05
95
449
95.0
STD
0903-0565 0910-0375
-
CW18
-
-
WR450F 03-06
x
97.0
2.00
-
-
-
-
-
-
13.5:1 Hi-Compression.
63.4
-
-
-
-
-
-
Nikasil Bore-Cylinder
sleeving or replating required for
-
-
-
-
-
-
oversizes. ArmorGlide skirt coated
YZ450F 06-09
95
449
95.0
STD
0903-0564 0910-0373
-
CW18
-
-
WR450F 07-15
x
97.0
2.00
-
0910-0374
-
-
-
-
12.5:1 Standard Compression.
63
-
-
-
-
-
-
Nikasil Bore-Cylinder
sleeving or replating required for
-
-
-
-
-
-
oversizes. ArmorGlide skirt coated
YZ450F 06-09
95
449
95.0
STD
0903-0566 0910-0375
-
CW18
-
-
WR450F 07-15
x
-
-
-
-
-
-
13.5:1 Hi-Compression.
63.4
-
-
-
-
-
-
Nikasil Bore-cylinder
sleeving or replating required for
oversizes. ArmorGlide skirt coated
-
-
-
-
-
-
YZ450F 10-13
97
449
97
STD
-
0910-2884
-
CW18
-
-
12.5:1 Stock Compression
x
-
-
-
-
-
-
Nikasil Bore-ArmorGlide skirt coated
60.8
-
-
-
-
-
-
YZ450F 10-13
97
449
97
STD
-
0910-2885
-
CW18
-
-
13.5:1 High Compression
x
-
-
-
-
-
-
Nikasil Bore-ArmorGlide skirt coated
60.8
-
-
-
-
-
-
HIGH-PERFORMANCE PISTONS continued on next page.
DISCLAIMER: NOT LEGAL FOR SALE OR USE IN CALIFORNIA ON ANY POLLUTION CONTROLLED MOTOR VEHICLES.
SEE PAGE 4 FOR IMPORTANT EMISSION DEFINITIONS AND REGULATORY COMPLIANCE AND WARRANTY INFORMATION.
2018 PARTS UNLIMITED OFFROAD