Honda 2006 RC51 Owner's Manual page 209

Specifications
Power Transmission
primary reduction
gear ratio, 1st
2nd
3rd
4th
5th
6th
final reduction
standard
sprocket sizes
final drive
202
Technical Information
1.700
2.461
1.812
1.428
1.240
1.080
0.962
2.500
drive (engine) sprocket:
driven (rear wheel) sprocket:
chain
DID 50VA8 or RK GN50HFOZ5
Classic Cycles Technical Resources
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