if I spun a bearing what do I need
 

13b Bridgeport 6port non turbo, if I spun a bearing on my back rotor what do I need to get. Its knocking badly now, on rev and off rev it's knocking what parts do I need to fix it up? New stationary gear or what. It's only my back rotor

You need to open it up to find out what you need. Remember there are two bearings back there, one on the rotor and one of the stat gear.

Knocking ?? who's knocking ?

disassemble it.
thoroughly inspect everything.
fix the root problem before reassembly.