A compressor assembly configured to be operatively coupled to differently dimensioned motor stators in a reciprocating compressor , the compressor assembly comprising: a cylinder forming a space for compressing a fluid; a crankshaft housing operatively coupled to the cylinder; a crankshaft housed within the crankshaft housing; a rod assembly configured to reciprocate within the cylinder so as to compress the fluid within the space, the rod assembly being driven by the crankshaft; characterized by a motor housing operatively coupled to the crankshaft housing, the motor housing comprising a first inner sidewall , a first outer sidewall , a second inner sidewall , a second outer sidewall , and an intermediate portion interposed between the first outer sidewall and the second inner sidewall, wherein: the first inner and first outer sidewalls form at least part of a first cylindrical shell , the second inner and second outer sidewalls form at least part of a second cylindrical shell , at least one of the first or second cylindrical shell is configured such that the first and second cylindrical shells have different axial lengths, and at least one of the first or second cylindrical shell is configured such that the first and second cylindrical shells have different radial lengths; and wherein at least a portion of the first inner sidewall and at least a portion of the second inner sidewall are configured to be coupled to an outer surface of a variety of different motor stators. a cylinder forming a space for compressing a fluid; a crankshaft housing operatively coupled to the cylinder; a crankshaft housed within the crankshaft housing; a rod assembly configured to reciprocate within the cylinder so as to compress the fluid within the space, the rod assembly being driven by the crankshaft; characterized by a motor housing operatively coupled to the crankshaft housing, the motor housing comprising a first inner sidewall , a first outer sidewall , a second inner sidewall , a second outer sidewall , and an intermediate portion interposed between the first outer sidewall and the second inner sidewall, wherein: the first inner and first outer sidewalls form at least part of a first cylindrical shell , the second inner and second outer sidewalls form at least part of a second cylindrical shell , at least one of the first or second cylindrical shell is configured such that the first and second cylindrical shells have different axial lengths, and at least one of the first or second cylindrical shell is configured such that the first and second cylindrical shells have different radial lengths; and wherein at least a portion of the first inner sidewall and at least a portion of the second inner sidewall are configured to be coupled to an outer surface of a variety of different motor stators. the first inner and first outer sidewalls form at least part of a first cylindrical shell , the second inner and second outer sidewalls form at least part of a second cylindrical shell , at least one of the first or second cylindrical shell is configured such that the first and second cylindrical shells have different axial lengths, and at least one of the first or second cylindrical shell is configured such that the first and second cylindrical shells have different radial lengths; and wherein at least a portion of the first inner sidewall and at least a portion of the second inner sidewall are configured to be coupled to an outer surface of a variety of different motor stators. <EOS>