The Miyota 8N24 is a skeletonized automatic calibre produced by Miyota (Citizen), a Japanese movement manufacturer. Operating at 21,600 bph in a 25.6mm diameter, 5.55mm thick architecture with 21 jewels and approximately 42 hours power reserve, it is one of the few Japanese automatic calibres designed from the outset with a skeletonized architecture — the movement bridges and rotor are shaped to expose the mechanical components beneath. The V3 designation refers to the third-generation modification of this calibre by replica manufacturers for compatibility with skeleton dial and exhibition caseback references.
In replica watches, the Miyota 8N24 V3 is used in two distinct contexts: skeleton dial references where the movement is visible through an open dial design, and exhibition caseback references where the movement is visible through a transparent caseback. In both cases, the skeletonized architecture of the 8N24 is the reason for its selection — it provides genuine mechanical visual interest rather than a decorative overlay. Unlike Mingzhu calibres used in skeleton-style references, the 8N24 V3 is a Japanese Miyota calibre with the reliability and serviceability characteristics associated with that manufacturer.
In Practice
- The 8N24 V3 operates at 21,600 bph with 21 jewels and approximately 42 hours power reserve — slightly longer than the DG2813 V4's 36-hour reserve. It includes both automatic winding through wrist motion and manual winding capability via the crown, with hacking (stop-seconds) for precise time setting.
- The skeletonized architecture is a factory design feature of the 8N24 — not a modification applied by replica manufacturers. The bridges, mainplate, and rotor are shaped to expose the movement's mechanical components, making the calibre visually appropriate for both skeleton dial and exhibition caseback applications without additional modification.
- Accuracy is rated at -20 to +40 seconds per day — a wider tolerance range than higher-grade Japanese calibres but standard for automatic movements in this production tier. Actual daily performance depends on regulation quality at the point of assembly by the replica manufacturer.
- The V3 designation reflects replica manufacturer modifications to the base 8N24 calibre — case fitment, rotor finishing, and dial compatibility adjustments for specific skeleton and exhibition caseback reference geometries. The core calibre architecture and performance specifications remain consistent with the base Miyota 8N24.
- As a Miyota calibre, the 8N24 V3 carries the serviceability advantages associated with Japanese movements — it is well-documented, recognizable to most watchmakers, and straightforward to service relative to Chinese clone calibres used in comparable skeleton references.
Related Terms
Miyota Movement · Mingzhu DG2813 V4 · Super Clone · Sapphire Crystal · Exhibition Caseback
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For a full overview of movements used in replica watches — including how the Miyota 8N24 compares to other calibres — read: Replica Watch Movements Explained