I have Hydrive with a high volume pump/helm (bit over one and a half turns lock to lock) and it changes constantly,not much,but would drive me mad with a knob.
No relief there Gazza - just a byproduct of design.
I have Hydrive with a high volume pump/helm (bit over one and a half turns lock to lock) and it changes constantly,not much,but would drive me mad with a knob.