I bought another 201k on the weekend. It's aluminium and a knee controlled beast. Just couldn't resist it for $29. Pretty sure the guy who sold it to me was lying when he said he didn't know how to use it, but the motor ran at full speed as soon as the switch was flicked. This is caused by the capacitors shorting out. The capacitors were used to prevent any interference from the motor affecting things like TV sets and radios. These days they're not really necessary since most devices have supression built in. Both foot and knee controllers have the same bits inside so instructions are the same.
So, just remove the four screws holding the base on, take the capacitors out like I did and your machine should be back to working. If yours is a knee controller, remove it from the case first. It's obvious how to do this.