bbs01 momentary whirring/slipping when starting up


Esteemed Pedelecer
Aug 22, 2017
Four Lanes,Cornwall
been researching til my brain bled,without success. This is something i cant remember if new or always been there. Really noticing it now tho . When i engage PAS or throttle from a standstill. There is always a kind of electronic/mechanical hum/whirring sound/sensation as if somethings slipping or taking a cpl moments to engage. Then off it goes accelerating smoothly.

I wondered if this is what people mean by a jerky throttle ,except its the PAS as well. So ive tried throttle on both 'current' and 'speed' modes,various start currents 10%-30%.PAS likewise tried 10% - 50% SC. Always the same.

thanks if anyone can shed some light.
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