SPEC
Item
Margin thickness (D)
Intake
Exhaust
Stem outside diameter
Intake
Exhaust
Guide inside diameter
Stem-to-guide clearance
Intake
Exhaust
Stem runout limit
Intake
Exhaust
VALVE SPRINGS
Free length
Free length limit
Tilt limit
PISTONS
Piston-to-cylinder clearance
Piston diameter (D)
Standard
Oversize
Measuring point (H)
Piston pin boss inside diameter
Oversize piston diameter
1st (except for USA)
2nd
PISTON PINS
Diameter
PISTON RINGS
Top ring
Type
Dimensions (B × T)
End gap (installed)
Wear limit
Side clearance (installed)
2nd ring
Type
Dimensions (B × T)
End gap (installed)
Wear limit
Side clearance (installed)
MAINTENANCE SPECIFICATIONS
Worldwide
USA
Canada
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
H
mm (in)
D
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
B
T
mm (in)
mm (in)
mm (in)
mm (in)
B
T
mm (in)
mm (in)
mm (in)
FT25BED
Unit
—
T25ER
5.475 - 5.490 (0.2155 - 0.2161)
5.460 - 5.475 (0.2150 - 0.2155)
5.500 - 5.512 (0.2147 - 0.2170)
0.010 - 0.037 (0.0004 - 0.0015)
0.025 - 0.052 (0.0010 - 0.0020)
37.85 - 39.85 (1.490 - 1.569)
0.035 - 0.065 (0.0014 - 0.0026)
64.950 - 64.965 (2.5570 - 2.5573)
65.450 - 65.465 (2.5768 - 2.5774)
15.974 - 15.985 (0.6289 - 0.6293)
15.965 - 15.970 (0.6285 - 0.6287)
0.15 - 0.30 (0.006 - 0.012)
0.02 - 0.06 (0.0008 - 0.0024)
0.30 - 0.50 (0.012 - 0.020)
0.02 - 0.06 (0.0008 - 0.0024)
– 9 –
Model
FT25BET
0.6 - 1.0 (0.024 - 0.039)
0.7 - 1.1 (0.026 - 0.043)
0.03 (0.0012)
0.016 (0.0006)
37.85 (1.490)
1.7 (0.06)
2 (0.08)
+ 0.25 (0.010)
+ 0.50 (0.020)
Rounded edge
1.2 × 2.4 (0.047 × 0.094)
0.5 (0.020)
Tapered edge
1.5 × 2.7 (0.059 × 0.106)
0.7 (0.028)
E
T25TR
T25TR