| Brand | Miyota (Citizen) |
| Caliber Number | 8218 |
| Movement Type | Automatic |
| Diameter | 11 1/2”’ (26mm overall) |
| Height | 5.67mm |
| Jewels | 21 |
| Vibrations Per Hour | 21,600 bph |
| Shock System | Parashock |
| Power Reserve | ~42 hours |
| Lift Angle | 49 degrees |
| Stem | 065-212 |
| Hand Size | 1.52mm / 1.0mm / 0.17mm |
| Winding Direction | Counterclockwise (uni-directional) |
| Hacking | No |
| Hand-Windable? | Yes |
| Functions | Hours, minutes, small seconds (at 4:00), date calendar |
| Country of Manufacture | Japan |
| Known Brands | Reverie Sea-Spirit, SD-09 UFO Spacecraft, AVI-8 Spitfire 300 (add yours in the comments below) |
The Miyota caliber 8218 is an automatic movement found in many microbrand watches.
Some of the topics covered in the caliber listing:
Miyota 8218 vs 8245:
The caliber 8218 has a date at 3:00. The caliber 8245 is the same as the 8218 but without a date complication.
Miyota 8218 vs 8219:
Similar to the caliber 8218, there is also a caliber 8219. They are essentially the same with exception to a 24 hour hand on the 2819 at 9:00.
Accuracy:
Miyota states that the caliber 8218 keep accuracy within -20～+40 seconds/day, with a posture difference of under 50 seconds/day.
Power Reserve:
The power reserve or running time when fully wound is about 42 hours. As for getting the full power reserve, Miyota says: The mainspring becomes fully wound by rotating the ratchet wheel 7.5 times or turning the crown 40 times.
Replacement Prices:
At the time of this post, replacement prices for the caliber 8218 were found online in the range of $40-50 USD.
Examples of watches with caliber 8218:
The example pictured below is from the crowdfunded SD-09 UFO Spacecraft watch.
Below is a custom airplane rotor found in an AVI-8 Spitfire 300 watch powered by a Miyota 8218 movement.
Additional Resources:
