Miyota Caliber 8285

Manufacturer	Miyota
Caliber Number	8285
Movement Type	Automatic, self-winding mechanical
Lignes	13”’
Diameter	29mm
Height	5.94mm
Jewels	21
Beat Rate	21,600 vph
Lift Angle	49 degrees
Power Reserve	42 hours
Rotor Winding Direction	Unidirectional, counterclockwise
Hand-Windable?	Yes
Anti-Shock Device	Parashock
Stem	065-212 (tap 10)
Hand Count	3
Hand Sizes	1.65mm / 1mm / .17mm
Functions	Central hours; central minutes; central sweeping seconds; day of the week at 12:00; date at 3:00
Hacking Seconds?	Unconfirmed
Quickset Date?	Yes
Country of Manufacture	Made in Japan
Known Models	(Add your watch to the comments below…)

The Miyota caliber 8285 is an automatic movement with a day-date complication. This movement is based on the cal. 82XX series of what Miyota calls their “Standard Automatic” line. It is made in Japan and has 21 jewels and a beat rate of 21,600 vph with a power reserve of about 42 hours.

Availability:

This movement is discontinued and no longer available from Miyota. You may still be able to find it from watch parts sellers.

Miyota Day-Date:

The calendar wheels on this caliber allow for a display similar to the Rolex Day-Date, with a panoramic full day of the week at 12:00 and date window at 3:00.

Examples of watches with this movement:

Watches with the 8285 include the MeisterSinger Urban Day Date, as well as this Cadisen Business Day-Date.

Additional Resources:

• Official tech drawings with dial feet location (pdf)
• Master List of Miyota calibers