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 #
YZ250 99-01
66.4
249
66.4
STD
0903-0921 804M06640 2614CD
CW18
S-508
B1003
Pro-Lite
x
67.0
0.6
-
0910-1244
2638CD
-
-
-
*Ceramic Composite-Cylinder sleeving or 72
67.5
1.1
-
0910-1245
2658CD
-
-
-
68.5
2.10
-
0910-0207
2697CD
-
-
-
66.4
249
66.4
STD
0903-0308 804M06640 2614CD
CW18
S-508
B1003
Pro-Lite
x
67.0
0.6
0903-0524 0910-1244
2638CD
-
-
-
*Ceramic Composite-Cylinder
72
67.5
1.1
-
0910-1245
2658CD
-
-
-
sleeving or replating required
68.5
2.10
0903-0188 0910-0207
2697CD
-
-
-
for oversizes
-
-
-
-
-
-
66.4
249.3
66.4
STD
0903-0929 0910-0367
0912-0106
CW18
S-508
B1003
250cc Racer’s Choice Single
x
-
-
-
-
-
-
Ring. Electra Coated
72
-
-
-
-
-
-
ArmorGlide skirt coated
-
-
-
-
-
-
DT400 75-78
85
397
85.0
STD
-
-
3347TD
CW18
S-277
B1003
x
85.5
0.5
-
232M08550 3366TD
-
-
-
70
86.0
1.0
-
232M08600 3386TD
-
-
-
86.5
1.5
-
-
3405TD
-
-
-
87.0
2.0
-
-
3425TD
-
-
-
YZ400 76-78
85
397
85.0
STD
-
-
3347TD
CW18
S-277
B1003
IT400 76-78
x
85.5
0.5
-
394M08550 3366TD
-
-
-
70
86.0
1.0
-
-
3386TD
-
-
-
86.5
1.5
-
394M08650 3405TD
-
-
-
87.0
2.0
-
-
3425TD
-
-
-
YZ465 80-81
85
465
85.0
STD
-
-
3347TD
CW18
S-277
B1014
IT465 81-82
X
85.5
0.5
-
451M08550 3366TD
-
-
-
82
86.0
1.0
-
-
3386TD
-
-
-
86.5
1.5
-
451M08650 3405TD
-
-
-
87.0
2.0
-
-
3425TD
-
-
-
YZ490 82-83
87
487
87.0
STD
-
478M08700 3425TD
CW18
S-277
B1014
IT490 83-84
x
87.5
0.5
-
478M08750 3445TD
-
-
-
82
88.0
1.0
-
478M08800 3465TD
-
-
-
88.5
1.5
-
-
3484TD
-
-
-
89.0
2.0
-
478M08900 3504TD
-
-
-
YZ490 84-90
87
487
87.0
STD
-
546M08700 3425TD
CW18
S-277
B1014
WR5091-93
x
87.5
0.5
-
546M08750 3445TD
-
-
-
82
88.0
1.0
-
546M08800 3465TD
-
-
-
88.5
1.5
-
546M08850 3484TD
-
-
-
89.0
2.0
-
546M08900 3504TD
-
-
-
YAMAHA 4-STROKE
47
90
47.0
STD
-
0910-0368
0912-0112
CW13
0913-0005
-
x
92
47.5
0.50
-
0910-0369
0912-0113
-
-
-
Cylinder boring required
51.8
94
48.0
1.00
-
-
0912-0114
-
-
-
for oversizes
110
52 .0
5.00
-
-
0912-0111
-
-
-
TTR125/L 00-17 (all)
54
123.7
54.0
STD
0903-0742 4752M05400 -
CW15
-
-
x
54.5
0.5
0903-0740 4752M05450 -
-
-
-
54
55.0
1.0
0903-0741 4752M05500 -
-
-
-
TTR250 99-06
73
249
73.0
STD
-
4689M07300 2874XC
CW18
-
-
10.5:1 Compression
x
73.5
0.5
-
4689M07350 2894XC
-
-
-
59.6
74.0
1
-
4689M07400 2913XC
-
-
-
77
249
77.0
STD
0903-0554 0910-0573
-
CW16
0913-0008
-
12.7:1 Compression (0903-0554/ 0910-0573) x
262
79.0
2.0
-
0910-0574
3110XG
-
-
-
13.2:1 Compression (0910-0574)
53.6
-
-
-
-
-
-
YZ250F 01-04
77
249
77.0
STD
0903-0561 0910-0806
0912-0140
CW16
0913-0008
-
13.5:1 Compression
x
263
-
-
-
-
-
-
Light weight, 2-ring, gas ported
53.6
-
-
-
-
-
-
ArmorGlide skirt coated
-
-
-
-
-
-
YZ250F 01-11
77
290
83.0
6.0
-
0910-2936
3268XG
CW16
0913-0008
-
x
-
-
-
-
-
-
12.5:1 Compression
53.6
-
-
-
-
-
-
290cc Big Bore
-
-
-
-
-
-
ArmorGlide skirt coated
-
-
-
-
-
-
77
250
77.0
STD
0903-0559 0910-0808
-
CW16
0913-0008
-
x
263
79.0
2.00
-
-
3110XG
-
-
-
12.5:1 Compression
53.6
-
-
-
-
-
-
Nikasil Bore-Cylinder sleeving or replating
-
-
-
-
-
-
-
-
-
-
-
-
YZ250F 05-07
77
250
77.0
STD
0903-0558 0910-0810
0912-0140
CW16
0913-0008
-
WR250F 05-13
x
263
79.0
2.00
-
-
3110XG
-
-
-
13.5:1 Compression
53.6
-
-
-
-
-
-
ArmorGlide skirt coated
-
-
-
-
-
-
-
-
-
-
-
-
for oversizes
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