JT Sprockets

Online Catalogue

Betamotor 350 Jonathan

2003 to 2010

Front Sprocket

Steel Front Sprocket

Part Number: JTF432

Teeth: 16 Check Availability

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

Lightweight Self-Cleaning Front Sprocket

Part Number: JTF432SC

Teeth: 16 Check Availability

Available Sizes: 13, 14, 15

Rear Sprocket

Steel Rear Sprocket

Part Number: JTR5

Teeth: 44

Available Sizes: 39, 40, 41, 43, 44, 45, 46, 47, 49

Drive Chain

Pitch: 520

Length: 122

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
111213141516
Rear Sprocket393.55
+28.9%
3.25
+18.2%
3.00
+9.1%
2.79
+1.3%
2.60
-5.5%
2.44
-11.4%
403.64
+32.2%
3.33
+21.2%
3.08
+11.9%
2.86
+3.9%
2.67
-3.0%
2.50
-9.1%
413.73
+35.5%
3.42
+24.2%
3.15
+14.7%
2.93
+6.5%
2.73
-0.6%
2.56
-6.8%
433.91
+42.1%
3.58
+30.3%
3.31
+20.3%
3.07
+11.7%
2.87
+4.2%
2.69
-2.3%
444.00
+45.5%
3.67
+33.3%
3.38
+23.1%
3.14
+14.3%
2.93
+6.7%
2.75
standard
454.09
+48.8%
3.75
+36.4%
3.46
+25.9%
3.21
+16.9%
3.00
+9.1%
2.81
+2.3%
464.18
+52.1%
3.83
+39.4%
3.54
+28.7%
3.29
+19.5%
3.07
+11.5%
2.88
+4.5%
474.27
+55.4%
3.92
+42.4%
3.62
+31.5%
3.36
+22.1%
3.13
+13.9%
2.94
+6.8%
494.45
+62.0%
4.08
+48.5%
3.77
+37.1%
3.50
+27.3%
3.27
+18.8%
3.06
+11.4%

Lower gear ratios allow for higher top speeds.

Higher gear ratios increase torque for better acceleration.

Full Gear Ratio Chart (pdf)