<p>Cycloid reducers are utilized extensively in a variety of industrial sectors as a standard transmission apparatus, and the reducers offer a variety of installation types to address distinct application scenarios. It should be noted that there are some discrepancies between the various installation types; therefore, this paper establishes a reasonable performance evaluation model for the two representative installation types of cycloid reducers and investigates the differences and similarities between the two different installation types in terms of performance. In specific applications, the most common and researched installation type contains fixed gear housing and flange with pins attached as output component. An alternative type contains fixed flange and gear housing as the output component. Nevertheless, research based on the latter installation type remains in its infancy, and the models for the evaluation of cycloid reducer performance in different installation types are lacking. In view of the above, this paper conducts theoretical modeling and numerical simulations to analyze and predict the performance of the reducers with two distinct installation types. Furthermore, the impact of design parameters on the performance of both installation types is studied. The parametric study includes clearances of gear pairs and pin pairs, number of gear teeth, and operating conditions, such as operating torques and lubrication conditions. Finally, an experimental study was conducted to validate the theoretical analysis. This paper provides a more comprehensive theoretical basis for the design and application of cycloid reducers.</p>