The cadence is defined by the respective gear ratio and the speed ridden. The Stromer standard gear ratios may be too small for flat route profiles. There is a desire for lower cadences. This can be achieved with a smaller rear pulley or a larger front pulley.
The ST2 / ST3 / ST5 / ST7 Pinion with the C1.9 or C1.12 gearbox uses a 39T pulley at the front and a 22T pulley at the rear.
There are larger pulleys at the front - but not with Pinion mounts. The rear might be possible. 20T(or 19T), but the rhyme would probably also have to be adapted?
The unfolding increases from 12.2 m (22T) to 13.5 m (20T) or 14.2 m (19T). With the standard configuration, the cadence at 45 km/h is 62, at 20T one of 56and with 19T one of 53.
From a sports medicine point of view, higher cadences are more optimal for the effort required and therefore also for the joints - but ultimately it's a matter of individual taste.
Cadence comparison Pinion / chain
If you want to know what the cadence is at vMax=45 km/h, here is a comparison of an ST3 with Derailleur gears and an ST3 Pinion C1.9.
Here you can see that the Pinion with a cadence of 62 requires around 10 revolutions/min less than the chain model with TF 72.
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