Value stream mapping (VSM) is a lean manufacturing (LM) technique used to examine the flow of materials and information for a particular product family. This paper aims to discuss the significance of VSM in an LM context in the gear manufacturing industry. The cycloidal speed reducer is one of the products that was chosen. There are 18 sub-components required for assembling the cycloidal speed reducer. The purpose of this research suggests a new approach of preferred multi-level VSM mapping based on manufacturing setup time reduction found in the gap analysis of the present state map. Using this idea, the study was conducted to determine the areas in which work in process, lead time, setup time, and cycle time need to be improved as part of developing a future state map and implementing Kaizen on the current state map. The results obtained from the study are as follows: The production lead time is reduced from 1131 to 1028 min, VA time was reduced from 323 to 308 min, and the NVA time was reduced from 671 to 582 min.