JT Sprockets

Online Catalogue

Yamaha FZR250 Genesis (2KR,2RF) — Japan

1989 onwards

Front Sprocket

Steel Front Sprocket

Part Number: JTF1263

Teeth: 17

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

Rear Sprocket

Steel Rear Sprocket

Part Number: JTR1847

Teeth: 55

Available Sizes: 46, 47, 48, 51, 55, 56, 57

Drive Chain

Pitch: 428

Length: 130

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
11121314151617
Rear Sprocket464.18
+29.3%
3.83
+18.5%
3.54
+9.4%
3.29
+1.6%
3.07
-5.2%
2.88
-11.1%
2.71
-16.4%
474.27
+32.1%
3.92
+21.1%
3.62
+11.7%
3.36
+3.8%
3.13
-3.2%
2.94
-9.2%
2.76
-14.5%
484.36
+34.9%
4.00
+23.6%
3.69
+14.1%
3.43
+6.0%
3.20
-1.1%
3.00
-7.3%
2.82
-12.7%
514.64
+43.3%
4.25
+31.4%
3.92
+21.3%
3.64
+12.6%
3.40
+5.1%
3.19
-1.5%
3.00
-7.3%
555.00
+54.5%
4.58
+41.7%
4.23
+30.8%
3.93
+21.4%
3.67
+13.3%
3.44
+6.2%
3.24
standard
565.09
+57.4%
4.67
+44.2%
4.31
+33.1%
4.00
+23.6%
3.73
+15.4%
3.50
+8.2%
3.29
+1.8%
575.18
+60.2%
4.75
+46.8%
4.38
+35.5%
4.07
+25.8%
3.80
+17.5%
3.56
+10.1%
3.35
+3.6%

Lower gear ratios allow for higher top speeds.

Higher gear ratios increase torque for better acceleration.

Full Gear Ratio Chart (pdf)