There is a desire for lower Cadences. Cadence is defined by the respective gear ratio and the speed at which it is ridden. For flat terrain profiles, the standard Stromer gear ratios might be too small. Lower cadences can be achieved with a smaller pulley at the rear or a larger one at the front.
For the ST2 / ST3 / ST5 / ST7 pinion with the C1.9 or C1.12 gearbox, a pulley with 39 teeth is used at the front and one with 22 teeth at the rear.
While there are larger sprockets in the front – but not with a pinion mount. In the back, one could use a disc with 20T or change to 19T, but the rhyme would probably have to be adjusted?
The deployment increases from 12.2 m (22T) to 13.5 m (20T) or 14.2 m (19T). With the standard configuration, you have a cadence of [cadence value] at 45 km/h. 62, at 20T one of 56, and at 19T one of 53.
From a sports medicine perspective, higher cadence is optimal for the exertion of force and thus for the joints – ultimately, however, it's individual and also a matter of taste.
Cadence comparison Pinion / chain
Here's a comparison of an ST3 with Derailleur gears and an ST3 Pinion C1.9 for the maximum speed of 45 km/h.
The cadence with Pinion is 62 revolutions/min, which is 10 revolutions less than with a chain drive.