Yamaha EH63 - Maintenance Specifications; Engine

MAINTENANCE SPECIFICATIONS
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SPECIFICATIONS
MAINTENANCE SPECIFICATIONS
ENGINE
Piston:
Piston-to-cylinder clearance 0.012–0.051 mm (0.0004–0.0020 in) (EH63K/EH64K/
EH64A/EH65B/EH65A)
0–0.042 mm (0–0.0016 in) (EH72A/EH72B/EH72K)
Limit 0.15 mm (0.0059 in)
Piston diameter 79.960–79.980 mm (3.1480–3.1488 in) (EH63K/EH64K/
EH64A/EH65B/EH65A)
83.980–84.000 mm (3.3062–3.3070 in) (EH72A/EH72B/
EH72K)
Limit 79.878 mm (3.1447 in) (EH63K/EH64K/EH64A/EH65B/
EH65A)
83.890 mm (3.3027 in) (EH72A/EH72B/EH72K)
Measuring point (from piston
skirt bottom)
13.0 mm (0.5118 in) (EH63K/EH64K/EH64A/EH65B/
EH65A)
10.0 mm (0.3937 in) (EH72A/EH72B/EH72K)
Piston pin hole inside diameter 21.002–21.011 mm (0.8268–0.8272 in)
Limit 21.041 mm (0.8283 in)
Piston pin:
Piston pin diameter 20.989–21.002 mm (0.8263–0.8268 in)
Limit 20.969 mm (0.8255 in)
Piston ring:
Top ring
Type Barrel
Dimensions 1.5 × 3.4 mm (0.0590 × 0.1338 in) (EH63K/EH64K/
EH64A/EH65B/EH65A)
1.5 × 3.6 mm (0.0590 × 0.1417 in) (EH72A/EH72B/
EH72K)
End gap (installed) 0.20–0.40 mm (0.0079–0.0157 in)
Limit 1.50 mm (0.0590 in)
Side clearance 0.05–0.09 mm (0.0019–0.0035 in)
Limit 0.14 mm (0.0055 in)
2nd ring
Typ e Ta p er
Dimensions 1.5 × 3.4 mm (0.0590 × 0.1338 in) (EH63K/EH64K/
EH64A/EH65B/EH65A)
1.5 × 3.6 mm (0.0590 × 0.1417 in) (EH72A/EH72B/
EH72K)
End gap (installed) 0.20–0.40 mm (0.0079–0.0157 in)
Limit 1.50 mm (0.0590 in)
Side clearance 0.03–0.07 mm (0.0012–0.0028 in)
Limit 0.13 mm (0.0051 in)