Some times, the drag is very slight, but at various times after a complete stop, the drag and noise would be much more pronounced. Still, not anything that could stop me from pedaling away. The noise and drag eventually dissipated to normal levels--what could cause this? I seem to recall a similar, higher drag when my batteries were at higher levels (58.8V).
Something doesn't sound quite right as the residual drag caused by the magnets moving past the stator should remain pretty consistent in relation to wheel speed. At very low speed, the drag is barely noticeable, but as the wheel speed increases, so does the residual drag effect.
It should make no difference whether the bike has been used consistently for hours or stood doing nothing for hours.
There should be no "physical contact" noise coming from the motor, if there is a scraping, binding or rubbing noise then it will need to be investigated to locate the cause.
There will typically be an amount of frequency induced harmonic noise coming from inside the motor as the rotating magnets cause the stator to vibrate slightly, the amount of noise is determined by the frequency of the passing magnets
(i.e. wheel speed) and is not greatly affected by the amount of throttle being applied.
I suggest you carefully listen for any signs of physical contact as the wheel is rotated slowly by hand to make sure that nothing is physically rubbing internally or externally
(i.e. the centre of the freewheel or tyre rubbing against frame, or insufficient clearance on the brakes etc.) To help overcome the effect of the motor's residual magnetic drag on a long ride, try setting the cruise control slightly below your typical riding speed and the motor should only draw a small amount of power from the battery when pedalling at your typical riding speed.
However, the power being drawn from the battery will increase significantly as your speed drops down to
(or falls below) the set cruise speed .
Alan
