My Mainline warship, bought second hand a couple of years back, has a motor problem I've not encountered before. When starting it hardly moves, needs a shove or two, or three, but eventually makes it slowly round a circuit. Then after another circuit or two it springs to life and performs just how you would expect. It seems to need to run for a few minutes to warm up. I've had it in pieces and cleaned it but with no affect, contacts etc all seem OK, so has anyone any other ideas?