Yamaha 2011 WR450FA, Owner'S Service Manual

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2-6
MAINTENANCE SPECIFICATIONS
Direction of winding (top view) (IN) Clockwise ----
Direction of winding (top view) (EX) Clockwise ----
Piston:
Piston to cylinder clearance 0.020–0.045 mm (0.0008–0.0018 in) 0.1 mm (0.004
in)
Piston size "D" 94.965–94.980 mm (3.7388–3.7394 in) ----
Measuring point "H" 8 mm (0.315 in) ----
Piston off-set 1 mm (0.0394 in) ----
Piston pin bore inside diameter 18.004–18.015 mm (0.7088–0.7093 in) 18.045 mm
(0.7104 in)
Piston pin outside diameter 17.991–18.000 mm (0.7083–0.7087 in) 17.971 mm
(0.7075 in)
Piston rings:
Top ring:
Type Barrel ----
Dimensions (B × T) 1.2 × 3.5 mm (0.05 × 0.14 in) ----
End gap (installed) 0.20–0.30 mm (0.008–0.012 in) 0.55 mm (0.022
in)
Side clearance (installed) 0.030–0.065 mm (0.0012–0.0026 in) 0.12 mm (0.005
in)
2nd ring:
Type Taper ----
Dimensions (B × T) 1.00 × 3.35 mm (0.04 × 0.13 in) ----
End gap (installed) 0.35–0.50 mm (0.014–0.020 in) 0.85 mm (0.033
in)
Side clearance 0.020–0.055 mm (0.0008–0.0022 in) 0.12 mm (0.005
in)
Oil ring:
Dimensions (B × T) 2.0 × 2.9 mm (0.08 × 0.11 in) ----
End gap (installed) 0.2–0.5 mm (0.01–0.02 in) ----
Item Standard Limit