Seiko 5 Sports Speed Timer 6139-7020 Chronograph

All you need to know about the rare JDM Chronograph – Versions, Dials, Bracelets

In the early stages of my collecting journey, I passionately desired to build a thorough collection. Not aiming for an overwhelming compilation of all Seiko watches, as that might be excessive, but instead, striving for a comprehensive set of Seiko timepieces that showcase the 6139 movement. Almost complete, with my initial emphasis on obtaining every dial variation of the Seiko 6139-7020, affectionately referred to as the Flying Saucer or Apple due to its distinct shape, crescent lugs, and unique scoops.

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Models & Versions 

The Seiko 5 Sports Speed Timer 6139-7020 Chronograph had a unique release with this reference number, without any variations intended for other markets. This exclusivity adds to its allure as the Seiko 6139-7020 was specifically crafted for the Japanese market, categorized as a JDM (Japan Domestic Market) watch. The movement consistently featured 21 jewels and an English/Kanji day wheel. Therefore, if you come across a watch lacking either of these characteristics, exercise caution, as it likely underwent some form of tinkering.

Here’s how they appeared in the early 1970s catalog.

Dials

The Seiko 6139-7020 Chronograph is available with dials in three distinct colors: champagne (7040T), black with black/blue sub-dial (7050T), and black with a champagne sundial (7040T). There is no documented information regarding the popularity or rarity of these dials. Ultimately, it’s a matter of personal preference. While I appreciate all three, I must admit that the champagne-colored dial holds a special place as my favorite, followed closely by the black one with a champagne-colored subdial, and then the other variant.

Seiko 6139-7020 (Champagne, Black Subdial)
Seiko 6139-7020 (Black, Champagne Subdial)
Seiko 6139-7020 (Black, Black/Blue Subdial)

Bracelets

During the 1980s and 1990s, it was a common practice to replace the original watch straps, either due to them being broken or simply for a change, often opting for leather alternatives. Initially, I didn’t pay much attention to these bracelets, but later on, I actively sought out the right bracelets for all my watches. I can attest that for some Seiko 6139s, finding the bracelet can be more challenging and costly than locating the watch itself. Part number of the matching bracelet of the first two models is XJA161, of the last one is XGA141.

Fortunately, with my cherished Seiko 5 Speed-Timer 6139-7020 collection, it wasn’t as demanding to find the bracelet. The same goes for obtaining all three variants of the dial, at least within Japan. As previously mentioned, it’s a JDM model, specifically designed for the Japan Domestic Market. While I do possess all the original bracelets, I have a preference for leather straps when wearing my 6139-7020s.

Movements + Hands

All these watches are equipped with the 6139 movement, with the earlier ones featuring the 6139A and the later ones incorporating the 6139B. According to information gathered from internet forums and other sources, the transition from the 6138A to the 6139B movement occurred around late 1971. While precise information is challenging to find, I attempted to deduce it based on my collection. All my Seiko watches from September 1971 had a 6139A movement, and some from October and November 1971 featured either a 6139A or a 6139B movement. However, all Seikos from December 1971 came with the 6139B, that applies to both, the 17J and 21J movements.

The Seiko 6139-7020, in particular, came exclusively with the JDM 21 Jewel movement. All three models shared the same set of hands, featuring yellow chronograph hands and black/white hour and minute hands. It’s truly a remarkable watch with a distinctive case shape, beautiful dials, and noteworthy bracelets. Owning one is a unique experience, and given its rarity, it’s advisable to acquire one before the market becomes saturated.

Check if I have one for sale – and if not – find one on ebay.

VINTAGE SEIKO WATCHES FOR SALE

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