Grail Watch Reference

A Reference Library for Watches from Grail Watch

  • Movement Database
  • Grail Watch Blog
  • The Watch Files Podcast
  • Reference Documents
  • About Grail Watch
  • Email
  • Instagram
  • LinkedIn
  • Twitter

Powered by Genesis

You are here: Home / Movements / Miyota 8285

Miyota 8285

Last Update: June 13, 2019

Brand:Miyota
Family:
Miyota 82/8N Series
Height:5.94 mm
Jewels:21
Reserve:42 hours
Frequency:21,600 A/h
Winding:Automatic, Central Rotor Automatic Winding, Counter-Clockwise Automatic Winding, Uni-Directional Automatic Winding
Diameter:29.20 mm (13 ligne)
  Complications:Date, Day, Hand Winding, Outer Day Wheel, Quick Date Correction
Hands:Central Hour Hand, Central Minute Hand, Central Seconds Hand, Date Window at 3:00, Day Window at 12:00
Distinguishing Technical Characteristics
Central-Rotor Automatic
Clockwise Balance Cock
Balance
Balance at 4:30
Central Rotor
Production:  – 
1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s 2000s 2010s 2020s

Part of the Miyota Cal. 8200 family, Cal. 8285 is a day-date central seconds automatic movement. Unlike the day-date Miyota 8205, Cal. 8285 features an outer day wheel, showing the day of the week in full at 12:00 instead of an abbreviation at 3:00. It is mono-lingual.

All members of the Miyota 8200 family have indirect seconds, which causes a noticeable wobble to the central seconds hand. When struck, the seconds hand can appear to pause for up to 2 seconds due to slack in the movement.

The movement can be manually wound with the crown in position 1. Rotate the crown clockwise to wind the mainspring.

The day and date wheels are advanced with the crown in second position (one notch out). Turn the crown counter-clockwise to advance the date wheel by one day. Turn the crown clockwise to advance the day wheel.

The date should not be set between 21:00 and 1:00 and the day should not be set between 1:00 and 4:30. Doing so risks damaging the movement.

The time is set with the crown in third position (pulled all the way out). Rotate the crown clockwise to advance the minute and hour hands and counter-clockwise to turn them backward.

No DateDate OnlyDay-Date
Hand Winding8270
8N33 SK
8260
Automatic
Central Seconds
8228A OH
82S0 PS OH
8N24 SK
8N26 SK HH
8210
8215 SR
821A
8200
8203
8205 SR
820A
8285 SR OD
Automatic
24 Hour Hand
8247
82D7 OH
8217
Automatic
Small Seconds
8245
82S5 PS OH
8N40 PS
8218
Automatic
24 Hour Hand
Small Seconds
82S7 PS OH8219
  • OH = Open Heart at 7:00
  • SK = Skeleton
  • PS = Partial Skeleton
  • HH = High Hands
  • OD = Outer Date
  • SR = Solid Rotor

Images are taken from official publications and are used here for commentary and educational purposes. Copyright is held by the original owner as noted.
Manufacturer Link

Related Posts

AS 5008

ETA 2893-2

Valjoux 88 VZHCL

Valjoux 72c VZHC

Zenith 682

ETA 2893-1