Rear Sprocket Moto Master 428 Fusion 47T red RM 85 / YZ 85

Funstion of Rear procket

The rear sprocket of a motorcycle is an essential part of the chain drive. It is mounted directly on the rear wheel and is connected to the front sprocket via a chain.

How can I tell if the sprocket is worn?

You can usually identify rear sprocket wear by inspecting the teeth. Worn teeth have an irregular shape and appear thin, very pointed or bent. You may also notice metallic rattling noises. Severe wear can cause the chain to skip because it slips over the excessively worn teeth.

smaller or larger Sprocket?

• Sprocket with more teeth → improved acceleration
• Sprocket with fewer teeth → higher top speed

You also have to consider the gear ratio between rear and front sprocket. The calculation is: number of teeth of rear sprocket / number of teeth of front spocket. A low ratio increases speed, while a high ratio improves acceleration.

Example: Front sprocket with 13 teeth and rear sprocket with 48 teeth: 48/13 = a ratio of 3.69.

Sprocket types

Steel is preferable to aluminium if you want the longest possible service life. Aluminium is the better choice for maximum performance because it is lighter. Self-cleaning anti-mud rear sprockets are suitable for off-road use in dirt and mud.

Chain care

To ensure optimal life, it is important that you do not neglect chain care, we recommend a special chain brush.

Overview of most common sprockets

• Sprocket, 62 mm internal diameter / 5-hole: Rieju (older models), Peugeot, Motorhispania
• Sprocket, 100 mm internal diameter / 4-hole: Beta RR50 from 2005
• Sprocket, 102 mm internal diameter / 6-hole 3x2: Derbi Senda DRD
• Sprocket, 105 mm internal diameter / 6-hole 3x2: Aprilia, Derbi, Gilera, Rieju, Peugeot, Motorhispania, Yamaha, MBK
• Sprocket, 108 mm internal diameter / 6-hole: Aprilia, Derbi, Gilera