Yamaha Motor Co., Ltd. YFM7FGPW — ENGINE SPECIFICATIONS

2 - 8 ENGINE SPECIFICATIONS SPEC Item Standard Limit Piston Piston-to-cylinder clearance Diameter “D” H D Height “H” Offset Offset direction Piston pin bore inside diameter Piston pin outside diameter Piston-pin-to-piston-pin-bore clear- ance 0.030 ~ 0.055 mm (0.0012 ~ 0.0022 in) 101.955 ~ 101.970 mm (4.0140 ~ 4.0146 in) 10.0 mm (0.39 in) 0.50 mm (0.0197 in) Intake side 23.004 ~ 23.015 mm (0.9057 ~ 0.9061 in) 22.991 ~ 23.000 mm (0.9052 ~ 0.9055 in) 0.004 ~ 0.024 mm (0.0002 ~ 0.0009 in) 0.13 mm (0.0051 in) ---- ---- ---- ---- 23.045 mm (0.9073 in) 22.971 mm (0.9044 in) 0.074 mm (0.0029 in) Piston rings Top ring B T Ring type Dimensions (B × T) End gap (installed) Ring side clearance 2nd ring B T Ring type Dimensions (B × T) End gap (installed) Ring side clearance Barrel 1.20 × 3.80 mm (0.05 × 0.15 in) 0.20 ~ 0.35 mm (0.008 ~ 0.014 in) 0.030 ~ 0.070 mm (0.0012 ~ 0.0028 in) Taper 1.20 × 4.00 mm (0.05 × 0.16 in) 0.75 ~ 0.90 mm (0.030 ~ 0.035 in) 0.030 ~ 0.070 mm (0.0012 ~ 0.0028 in) ---- ---- 0.60 mm (0.024 in) 0.12 mm (0.0047 in) ---- ---- 1.25 mm (0.049 in) 0.13 mm (0.0051 in)