Is this a DC machine?
We don't really see the Prime Mover stuff here in Europe but from what I gather bit's of it are based / used on the older BT machines.
If it is a DC machine & if it is the same drive system as BT Europe use I'd check the microswitch inside the throttle pedal assy as the roller wheel can get a flat spot & cause odd issues like this.
Is this the grey Atlas Copco transistor regulator with 1 green, 1 yellow & 2 red led's fitted?
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