I'm trying to get a Rimfire to run but it won't. I have the Bl-8 speed control and 640 3-cell Lipo. Servos work and speed control has been programmed, several times, but when I give the motor throttle, it turns very slowly, maybe 1 revolution in 3 seconds and makes an awful grinding noise. I have adjusted transmiiter settings, timing, and everything else I can think of but it still does the same thing. I have eliminated a bad lead by disconnecting the motor leads one at a time and with any one lead disconnected, the motor just quivers a little. Bad Motor?

You might have bad motor/ESC connectors.....there is the possibility that one or more of them have a cold solder connection.
if that is not the issue they might be touching each other, i have had that happen and it makes that weird chattering you described.
I would start by re-saudering all the connectors. Chances are thats yer problem.

Tyler, after discussing the problem with GP, they send send it all back. Should see a new one in about 2 weeks. In the meantime, I'll be making a long trip to the HS to buy replacement.