Secondary gears -MALOSSI- Piaggio 125-150cc - 15/41 = 1:2.73

Extending the gear ratio makes sense if the engine power has been increased by successful tuning measures. With the extended gear ratio, you can convert your additional power into more speed.
In addition, the cylinders and the rest of the engine are protected, because they no longer have to be turned up so high.
In series engines, a longer gear ratio is usually not useful, because the power in most cases is not enough to convert the ratio plus into top speed.

Only suitable for vehicles with splined secondary shaft.