Miyota Citizen Caliber 8204 8204a

Miyota (Citizen) Caliber 8204

Miyota Citizen Caliber 8204 8204a

Manufacturer Miyota (Citizen)
Caliber Number 8204, 8204A
Movement Type Automatic, self-winding mechanical
Linges 11.5”’
Diameter
25.6mm
Height 5.67mm
Jewels 21
Power Reserve
~42 hours
Vibrations Per Hour
21,600 bph
Lift Angle
49 degrees
Rotor Winding Direction
Counterclockwise (uni-directional)
Hand-Windable? Yes
Hand Winding Direction
Clockwise (forward)
Shock System Parashock
Plastic Parts?
Yes
Functions Central hours, central minutes, central seconds, bi-lingual day/date calendar at 3:00
Hacking? Yes
Country of Manufacture Japan
Known Brands
Citizen Promaster Fugu (Too many to list, add more in the comments below…)

The Miyota caliber 8204 (8204A) is a 21 jewel automatic movement, first introduced in 1977 (other versions as early as 1974). This movement is from the Miyota 8200 family (aka 8 or 82 series) of movements.

This 8204 has either been discontinued by Miyota, and is no longer offered in their catalog of movements – or it is a Citizen-only movement not available for wholesale to parts sellers or watch brands.

The movement pictured above was submitted by Kyle, found in a Citizen Promaster ref: NY0140-80E. Although it is a Miyota caliber (Miyota is owned by Citizen), it is signed Citizen Watch Co. Although Miyota is owned by Citizen, typically the two brands will use slightly different caliber numbers to distinguish between Citizen branded watches and movements sold by Miyota to other watch brands. As we can see with the Promaster, both Citizen and Miyota are using the same caliber number designation for the 8204A.

A similar movement would be the current Miyota caliber 8205.

Miyota 8204 VS 8203:

There is a similar Miyota caliber 8203. These two movements are so similar that Citizen even combines them into one instruction manual. One main difference between the calibers is hacking (the second hand stops while setting the time, for precise time setting): The 8203 does not hack, whereas the 8204 does. Citizen officially refers to this as a second hand stop function.

Another difference is that the 8203 has a power reserve of 40 hours and the 8204 offers a power reserve of about 42 hours.

Accuracy of the 8203 is slightly better than the 8204 at -10/+20 sec/day vs -20/+40 sec/day for the 8204.

Interesting observation: There are some Citizen watches (such as the NY0040/NY0045 divers) that are supposed to have non-hacking caliber 8203 movements inside, but some collectors are reporting that their watches are powered by the hacking 8204 despite the dial (and possibly caseback) referencing the 8203. Please comment below if you have come across a watch like this.

Time and Calendar Setting:

  • You can hand wind the movement while the crown is in position 0.
  • Pull the crown out one click to position 1 to set the calendar. Turn the crown clockwise to advance the day of the week. Rotate the crown counterclockwise to advance the date.
  • Pull the crown out again (position 2) to set the time.
  • Do not set the date while the time is between 9:00pm and 4:00am.

Note: Although the 8204 has a quickset date, this does not mean the date instantly flips over at midnight. In fact, the changeover is not instantaneous, so do not be alarmed if you see a partial date when the hands are before or after 12:00AM.

Accuracy Rating:

As mentioned above, according to Citizen, the claimed accuracy rating of the caliber 8204 has an average daily difference of -20 to +40 seconds/day.

Replacement Prices:

The Miyota caliber 8204 has been discontinued, therefore replacement retail prices are not available. To find this movement, you will need to find a watch parts retailed with remaining new old stock, find a watch with this caliber inside, or possibly upgrade to a newer version.

Pros and Cons:

Pros:

  • Hacking
  • Long history of being built on a dependable movement framework
  • Affordable even when replacing with the newer version

Cons:

  • Some do not like the possible hesitating seconds
  • Discontinued so it’s not easy to find an exact 8204 replacement

Additional Images:

The example shown below is of a cal. 8204A found in this Citizen Promaster Fugu black and blue diver.

Citizen 8204a Fugu Movement Citizen Cal 8204a Fugu Movement Citizen 8204a Fugu Movement Rotor Macro Citizen 8204a Fugu Movement Balance Wheel Macro

Additional Resources:

You are reading Caliber Corner, the world's most popular resource for watch movement pics, specs, mods and DIY repairs. Follow @calibercorner on Twitter, Instagram but NOT Facebook. Subscribe on YouTube. Join our mission to spread movement awareness!

Join the discussion on Miyota (Citizen) Caliber 8204?

  • Keep comments respectful and follow our community guidelines.
  • Keep comments on the topic of Miyota (Citizen) Caliber 8204

For off topic or general watch questions, post in the Caliber Corner Forum.

guest

45 Comments
oldest
newest most voted
Inline Feedbacks
View all comments
Mr T
Mr T
2 years ago

My NY0086-16LE bought late December 2021 came with 8204. Says 8203 on the dial, and 8204 on the caseback.

Sunny
Sunny
1 year ago
Reply to  Mr T

My NY0085-19e is also same..

Pawel
Pawel
1 year ago
Reply to  Sunny

You have caliber 8204, caseback says truth.

Dadou
Dadou
1 year ago
Reply to  Pawel

The movement says the truth. Not the dial. Not the caseback. Check the movement!

juan
juan
2 years ago

January 2022 NY0040-09E reporting here, 8204 on the back, hackable, says 8203 on the dial.

Jeff McKean
Jeff McKean
2 years ago

I just got a NY0040-17L and it also hacks, but still says 8203 on the dial. Nice bonus!

Jeff McKean
Jeff McKean
2 years ago
Reply to  Jeff McKean

Oh and it DOES say 8204 on the caseback!

Oscar O’ Sullivan
Oscar O’ Sullivan
3 months ago
Reply to  Jeff McKean

My NY0040-17L is the same. Maybe it will be a collectible feature some day.

Mike
Mike
2 years ago

My NY0085-19E (purchased Jan 2022) has the hacking 8204 movement. 8204 is printed on the case back, but 8203 is printed on the dial.

Nick Kafir
Nick Kafir
2 years ago

Purchased a Citizen Promaster automatic (NY0040-17LE )February of 2022 through Amazon UK. Has 8203 on the dial and 8204 on the case back. Given that it has hacking it appears to be the 8204 movement.

Scott
Scott
2 years ago

Yes, I also have a Promaster dive watch that hacks. The back says 8204. The front says N-8203-917165-EY. Not sure what the actual model number of my piece is. I don’t see an NY# anywhere on it.

Emil
Emil
2 years ago

NY0085-86EE, bought in March ’22 in Serbia, at a reliable dealer store (decade-long experience, many stores)

front face says 8203, back says 8204… it is however hackable, so def 8204

My only explanation is that Citizen doesn’t care that much for such details in low-cost watches – I suppose they had a ton of produced dials, or didn’t care about changing the prepress data… 😀 whatever the case, I also don’t care that much… it looks nice and is pretty accurate (around -3 sec/day when wearing).

great bang for the buck!

Nunz
Nunz
2 years ago

Just got an ny0040-09w – it’s has 8203 on the front and 8204 on the back. It is hackable… so I guess it’s the 8204. Only had it a day… hopefully the power and accuracy stacks up to what you’re all experiencing.

Jeffrey Clement
Jeffrey Clement
1 year ago

Got an 8215 miyota movement in most of my collection and they are very accurate.

Logan
Logan
1 year ago

I recently bought the Promaster Diver Titanium with the green bezel (NY0071-81E), this is the Japanese version of the one Citizen has listed on their website with the black bezel. It says on the dial it has the 8203 movement but on the back of the watch, the caliber number says 8204. But, after reading the description you gave of the two calibers I think mine is actually an 8203 because of the time variance per day. Definitely very interesting that my watch has both 8203 and 8204 markings though.

letuan
letuan
8 months ago
Reply to  Logan

hey dude, although a bit late to the problem, but does it hack

Anastazy
Anastazy
1 year ago

I recently acquired a citizen NY0086-16L made in January 2021, which in the dial refers to movement 8203, yet at the back engraved is movement 8204. The watch hacks, so there is definitely an 8204 inside.

Carpetcop710
Carpetcop710
1 year ago

Same story here. Bought an NY0085-86E in May of 2022. The dial says 8203 however the case back says 8204 and the watch is hackable. Kind of a neat factory mistake that adds to the charm of a great dive watch at an incredible value.

Jeremiah B Leonard
Member
1 year ago

It says that the rotor wines in a counterclockwise direction. Is this if the back of the watch is facing me? And so, is actually clockwise if you’re talking about the face of the watch?

Jason
Jason
3 months ago

It is winding counter clockwise when looking at the back of the watch, looking at the rotor. There is a triangle on the rotor in the photos above that shows the winding direction. It is the same direction as the 8205 movement which has a clearer arrow on the rotor.

Diego
Diego
1 year ago

Same here. Bought me a NY0040-17LE last month (May 2022) in Germany. Dial says “8203” though it’s hacking and the back says “8204”.
Accuracy is +8sec/day at the moment, that’s okay for me.

Diogo
Diogo
1 year ago

Purchased a Citizen Promaster automatic (NY0040 )march of 2022 in Germany. Has 8203 on the dial and 8204 on back. Hacking works.

KyleR
KyleR
1 year ago

I bought a Citizen NY0140‑80e (2021 Fall Winter Collection) which has 8204 on the dial and caseback. If the movement is no longer in production as explained above, did Citizen release this model at the end of 2021 simply to deplete their 8204 inventory?

Andrew
Andrew
1 year ago

Am I the only one who thinks it’s strange that the movement is winding when you screw in the crown? Is that normal? What do others think?

Andrew
Andrew
1 year ago
Reply to  calibercorner

Ahh okay thank you for this! I just purchased the full lume dial NY0040 that on the dial has the 8203 marking but on the case back has 8204 and hacks (not so uncommon as it seems others have this as well). I was a bit shocked by the crown when I was setting the time because it still winds when screwing it down. It just doesn’t feel as smooth and easy as my skx and so I wasn’t sure what was going on. Thanks!

PrettyNiceWatches
PrettyNiceWatches
1 year ago

NY0040-09w, purchased July 2022. Hacks, says 8203 on the dial and 8204 on the case back.

Norman Gremore
Norman Gremore
1 year ago

“The newly reimagined Promaster Dive Automatic men’s watch by Citizen goes deeper into the history of the original version of this diving watch that was released in 1989 for the new generation of dive watch enthusiasts. A design element that stands out is the distinctive, serrated bezel design that was inspired by a fugu, the Japanese name for pufferfish. Featuring a 3-piece, 44mm case, anti-reflective sapphire crystal and a two-tone silver- and gold-tone stainless steel case and bracelet, the dark blue rotating bezel with a gold-tone easy-grip aluminum ring surrounds the black dial and luminous hands and markers, while the case… Read more »

h3o
h3o
1 year ago

Citizen started putting 8204s in the NY0040 line-up in 2021. The case back is easier/cheaper for them to update than the dial, hence why the dial still says 8203.

Brett Friedli
Brett Friedli
1 year ago

My Promaster NY0040-17LE has the 8204 movement in it.

John
John
1 year ago

Citizen tends to use parts in its Promaster “fugu” series until they run out so it’s not uncommon to find one with brighter hands than the dial. All of them have a green pip on the bezel regardless of the lume color used on hands or dial and in recent years the pip is noticeably brighter and longer lasting than on the hands or dial.

Rachel
Rachel
1 year ago

It took me purchasing 2 Citizen NY0085’s and finally sticking with a titanium NY0100 to realise that the rotar (hope that’s the right word – I’m referring to the the metal ‘half moon’ in the movement that usually contains the maker’s name!) is not broken, it’s just really, really noisy!! I sent the NY0085’s back after just a couple of days wear. If I moved my arm too quick it sounded like a little helicopter taking off. The NY0100 is similar, but not quite as audiable. Maybe the different metal is dampening the sound? I have owned many cheaper (under… Read more »

Rachel
Rachel
1 year ago

I think this Miyota, or a similar hacking day-date one, is in the Expedition North Titanium Automatic 41mm by Timex.

That’s also one loud watch to wear!

Marty
Marty
1 year ago

can the 8204 be regulated/calibrated to be more accurate time keeping?

Scott
Scott
10 months ago
Reply to  Marty

Yes, you can regulate it. I’ve gotten mine to about -7s/day. The mechanism is very touchy, so it will probably take many tries and many misses to get it where you want it. Another issue that makes it difficult is that I use a phone app to measure the beat rate and for some reason it has a very difficult time in picking up the sounds of my NY-0086 movement. So, I just make a slight regulation and wear it for a couple days to see how it runs. And repeat.

sjd
sjd
1 year ago

My 8204 movement in the promaster feels rough when I adjust the day. Date is fine. Need a bit more force to change the day. All the units I tested with the seller feels the same. Does anyone experience the same. My Seikos are pretty smooth.

jaggal16
jaggal16
5 months ago
Reply to  sjd

I just got a pro master with this movement and I have to say, the watch feels rough when adjusting the day, just like yours. I have to turn it the other direction while partially through to change the day without what feels like destroying the watch gears! Even when adjusting the time I hear an audible and unpleasant click, which I sometimes hear on my seiko 5 7s26 and 4r36. Are these sounds normal, I just want to make sure I’m not breaking anything?

JouWen
JouWen
1 month ago
Reply to  jaggal16

Received my first ever Citizen model Promaster NY-0086-85E Coke bezel 2 days ago. Experiencing the same quirk/issue and has been doing like you did if I need to change the day.
Weird that this occur to a mass production caliber that is not new.

Alberto
Alberto
8 months ago

Quería sabéis que tal es el calibre 8204, porque tiene tanta oscilación?.

fpurin
Member
3 months ago

I have a Citizen Promaster Diver NY0158 bought April 2023 in USA. Reports caliber 8204 in the back. Hacks. I like it very much and use it all the time. Since some weeks now, from time to time ( randomly every 2 days or so ) it starts to vibrate quite strongly for some 15 seconds then the vibration slowly fades away. Does someone know what it this? What causes it? Is it a bug or a defect? Should I worry about the watch or it is a “normal” behavior? Any help / information is welcomed, as I found nothing… Read more »

Beltruce
Member
3 months ago

Can I replace 8204 Caliber on my Citizen Promaster automatic (NY0040-17LE ) with the newer 8205 Caliber? Thx

Jason
Jason
3 months ago

I have a black dial Ny0040-09e and also the full lume dial version. They both have 8204 movement, have 8204 on the caseback but 8203 on the dial. Both bought from eBay vendors around October 2023. Accuracy is very good around +1 sec/day with constant wear but if I go for a 1 hour run with it on it will gain about 5 seconds.

Adam B
Adam B
23 days ago

Sneaky good movement in modern form. Out of box accuracy at consistent -10 SPD on a NY0135 series Fugu. My first ever attempt at watch regulation has this example running less than -1 sec per day (loses two-ish seconds on wrist and almost gains them back over night, dial up). Now running -14 seconds over the last twenty one days of daily wear.

Maybe not typical, and maybe wont last – but this is remarkable enough to have me heavily scrutinizing my future watch needs and desires.

Alican
Alican
7 days ago

Consistent movement, i have 2 Citizen Promasters with this, runs well within +10 seconds range, very good beat error and competes well against my Seiko 6r and Sellita sw200 movements. 2 and half years of use and no visible problems.

Seagull Caliber St19

Join our mission to spread movement awareness!

Members Online

  • keepthetime pc1093

Recent Forum Posts

Trending Comments

2

Sellita Caliber SW200 VS SW200-1

Wow man, you should join the R0l3X club, they're desperately looking for new members, but…


I_Am_Watcher
2

Sellita Caliber SW200 VS SW200-1

Basically you are saying that one of the world's most used workhorse movements is complete…


ggibby
2

Slava Caliber 2427

Lum-Tec gave up trying to fix my C2 with this movement, now I'm trying to…


Jeremiah B Leonard
1

ETA Caliber 955.414

I have one in Gucci watch, says Swiss. See photo….


admin
1

Seiko Caliber 6N52

Thank you for sharing with the community.


Sponsors

45
0
Would love your thoughts, please comment.x
()
x