JT Sprockets

Online Catalogue

Yamaha YZ125 A/B/C — USA

1974 to 1975

Front Sprocket

Steel Front Sprocket

Part Number: JTF1263

Teeth: 15

Available Sizes: 11, 12, 13, 14, 15, 16, 17

11 and 12 tooth versions do not feature bolt holes

Rear Sprocket

Part Number: TBA

Teeth: 47

Available Sizes:

Drive Chain

Pitch: 428

Length: 112

Please note that the chain shown in this listing is for size reference only. For the correct chain type and grade, please refer to the vehicle's manufacturer manual.

Gear Ratio Chart

TeethFront Sprocket
15
Rear Sprocket473.13
standard

Lower gear ratios allow for higher top speeds.

Higher gear ratios increase torque for better acceleration.

Full Gear Ratio Chart (pdf)