Other Watchy Bits: The Omega Speedmaster 125

While Omega has been crafting watches from their comptoir d’établissage in La Chaux-de-Fonds since 1848, the Speedmaster line of chronographs is a product of the 20th century. Born trackside into adrenaline-charged air and the oily scent of motor fuel, the Speedmaster was originally designed as a racing watch. Its unique tachymetre was meant to calculate automobile speeds over distance. But the timepiece had loftier goals. Willy Schirra was the first astronaut to wear a Speedmaster into space aboard the Sigma 7, which orbited the Earth six times in 1962. However, it wasn’t until 1965, after a series of stringent tests that the Speedmaster was adopted by NASA (over Breitling, Rolex, and Longines-Wittnauer) as the official watch of the space program.

Omega Speedmaster 125 378.0801 Review
Omega Speedmaster 125th Anniversary Edition 378.0801 @calibre321

Since then, the Speedmaster has accompanied Ed White on the first spacewalk and Buzz Aldrin as he stepped from Apollo 11 to the surface of the Moon. Proving its worth, the Speedmaster was also used by Jack Swiggert aboard Apollo 13 to time the all-important 14-second burn which allowed the crippled ship to safely return to Earth.

Omega Speedmaster 125 378.0801 Watch Review
World’s First COSC Certified Automatic Chronograph @calibre321

Over the years, the watch has been iterated upon in dozens of manners. It has even been “reduced.” The importance of the Speedmaster Collection to Omega is impossible to exaggerate. In fact, in 1973, when the brand was celebrating its 125th birthday, Omega chose to commemorate the occasion with a special issue of the timepiece—The Speedmaster 125 (ref. ST 378.0801).

Omega Speedmaster 125 378.0801 Watch Review
Controversial design @calibre321

Arguably, more than any other reference, the story of the Speedmaster 125 is fraught with controversy. It has been both praised for its ingenuity and denounced as design failure. On one hand, it is the world’s first, chronometer-certified automatic chronograph. On the other, it is also among the largest and the heaviest of all Speedmaster models. It has been billed as “chunky,” “unwieldly,” and “difficult to wear.” According to Omega, only 2000 examples were ever produced; however, anecdotal reports place that number as much as ten times higher than originally advertised.

So, what do I think? Well, I think this watch is the bomb. And I just bought one.


Omega Speedmaster 125 378.0801 Review
Stainless steel applied logo with a unique running seconds/24-hour register @calibre321

To be fair, I have been shopping for a Speedmaster for over a year now. Of course, the Professional was at the top of my list. But I have also had a thing for the Broad Arrow. Recently, an immaculate Day Date popped up in my Chrono24 feed (on Canadian soil!). I also looked closely at the Mark Series—particularly the Mark II. But something intangible played into my final decision. In March, I will clock a half century. The Big Five-O.

So, when a lovely example of the Speedmaster 125 came my way, I thought, what better way to celebrate 50 than with the purchase of a birth year watch?

Omega Speedmaster 125 378.0801 Watch Review
The Omega Speedmaster 125 was produced from 1973 until 1978 @calibre321

Now, the Speedmaster 125 was actually produced from 1973 (like me) until 1978. And, in truth, my watch pulled off the parking lot in May of 1974, according to its serial number. But let’s not split hairs. Next year, when Omega turns 175, I will be toasting them with my Speedmaster 125.

Omega Speedmaster 125 378.0801 Review
Brushed case with polished chamfers and bezel @calibre321


The Speedmaster 125

Like the Mark Series of Speedmasters, the 125 is a brutish iteration. It measures 42mm in diameter (45mm including the crown) and 51mm lug to lug. It’s also 16mm thick. To look at it, you might think someone chopped it out of a solid block of 316L stainless steel. Tonneau-shaped and predominantly brushed, the watch sports a finely polished chamfer along both the top and bottom edges of the mid-case. The stationary bezel is also buffed to a mirror-like shine.

Omega Speedmaster 125 378.0801 Review
Omega Speedmaster 125 on a 6 ¾” wrist @calibre321

Designed by EPSA—of compressor fame—the case is modular and, as such, can be pulled apart with the removal of the screw-down case back. Inside, a secondary case contains the movement, dial, and crystal as one piece. The back is embossed with Omega’s ubiquitous Hipoocampus and inside it has been engraved with, among other information, “Brevet 508925”—the Swiss patent number. The circular pushers and signed, knurled crown are partially protected by the slab of the outer case.

Omega Speedmaster 125 378.0801 Review
Modular EPSA case with integrated bracelet @calibre321

Unlike other Speedmasters, the 125 has an integrated bracelet, as well. It is entirely brushed and appears like an extension of the case. It tapers significantly and snake-like from 26mm at the case to a rather svelte 15mm at the clasp. At the top end, it is 6mm thick and the whole thing is held together by a series of spring bars. Despite its size and weight, the bracelet is surprisingly comfortable. The signed clasp has 8 increments of micro-adjust which help achieve the perfect fit.

Other than the unique case, for me, the dial is the highlight of the Speedmaster 125. Its tachymetre is laminated to the back of the mineral glass crystal, so that it appears to float above the watch below. Around the outer chapter ring, there is a printed second and minute index with baton-style markers on the fives. These markers, along with the pencil and syringe-styled handset are treated with tritium paint—as attested to by the “T” indicated in the text at the bottom. Unfortunately, although they do retain some evidence of that original colouring, the lume has now become inert.

Omega Speedmaster 125 378.0801 Review
Original tritium lume has become inert @calibre321

Of particular note are the Omega logo, brand name, and the number 125, which are fashioned from polished steel and applied under the twelve position, circumscribing the “Speedmaster” text. These pieces are all applied individually—rather than as a single appliqué—and at certain angles they really catch the light and cut through. Unlike the sub-dials on the Speedmaster Professional—which appear at 3, 6, and 9—the Speedmaster 125 employs an asymmetrical, two register layout at 6 and 9 only. The bottom index tracks up to 12 hours, while the upper register acts as both a running seconds and unique 24-hour indicator. The watch uses a central seconds, like many chronographs, but also a chronograph minute counter, as well—for a total of four hands on the dial. This particular model has tropicalized ever-so-slightly, from black to a deep grey-brown. There is a date wheel at three.

The crowning achievement of the Speedmaster 125, however, has nothing to do with its aesthetics. Its claim to fame is as the world’s first chronometer-certified automatic chronograph. The 1041 movement developed for this was based on the Lemania 1340, which was produced exclusively for Omega, and marketed as the calibre 1040. The 1040 appeared in a number of Seamasters and Speedmasters; however, the 1041 would be used exclusively in the Speedmaster 125. The calibre 1041 differs from the 1040 in only three visible ways—all of which involve the text stamped on the rotor and bridges. It is a 22-jewel, 4Hz movement with an Incabloc shock protection system and a 44-hour power reserve.

Omega Speedmaster 125 is the only watch to use the COSC certified calibre 1041 @calibre321



Despite the onset of the quartz crisis, the Speedmaster 125 appears to have sold well. The export of Swiss watches peaked in 1974, but eventually eroded under stiff competition from Japan and less expensive quartz technology. Its share of the US market would plummet from 92% to a low of 15% by 1984.

Retailing for much more than the Speedmaster Professional, the Speedmaster 125 managed to initially buck the trend of declining sales. In fact, its success might have been prescient as a guidepost for the Swiss industry, which was to reposition itself as a purveyor of luxury goods and not simply everyday watches.

Omega Speedmaster 125 378.0801 Review
Omega reports that only 2000 Speedmaster 125s were ever produced, but true numbers may be as high as 20 000 @calibre321

Space Exploration

Speedmasters and space have a deep connection. The Speedmaster 125 is no exception. Despite never having been officially cleared by NASA, the 125 did adventure to the cosmos on two occasions. Both times it was worn by Soviet Cosmonaut Vladimir Dzhanibekov. The Speedmaster 125 was on his wrist in 1978 during his training for Soyuz 27. He wore it again in 1982 during his flight on Soyuz T-6 and his sojourn on the Salyut 7 space station.  In total, Dzhanibekov spent 145 days in space and logged more than 8 hours of extra-vehicular activity.

Omega Speedmaster 125 378.0801 Review
Soviet Cosmonaut Vladimir Dzhanibekov and his Speedmaster 125 (Source)

Thoughts and Impressions

I won’t lie and say that I didn’t fret over my decision to procure the Speedmaster 125. Even after I pressed “purchase,” I spent a lot of time wondering if I had made an error. The next best thing to owning a new watch is hunting for one. Once the hunt was over, I felt momentarily deflated. But the moment I opened the box, I felt an immediate connection to the Speedmaster 125. My fears about its size (I have a 6 ¾” wrist), were grossly exaggerated. It’s a watch with real character. It’s rugged and refined at the same time. It’s also a little piece of horological history at my wrist.  

Omega Speedmaster 125: Big, Bold, and Beautiful @calibre321

In the end, I look at the Speedmaster 125 as I do the Ploprof or the Flightmaster. Yeah, it’s big. But it’s cool. Heck, it’s smaller than a number of watches today. Just look at the Rolex Deepsea—or, Heaven forbid, the Deepsea Challenge. Name your Breitling. History will not remember the abovementioned watches as design failures. Quite the opposite. I understand the draw of the Speedmaster Professional, aka The Moonwatch. I haven’t ruled that one out for myself, by any means. But the Speedmaster history is a treasure trove of “misfits” that offer incredible value for those who dare venture beyond the pale. This may be my first Speedmaster. But it won’t be my last.

Omega Speedmaster 125 378.0801 Review
Omega Speedmaster 125 @calibre321

For more information about the history and technical achievements of the Speedmaster 125, be sure to check out the work of Grégoire Rossier and Anthony Marquié, or Andy Kulas.

About the author

Brent Robillard is a writer, educator, craftsman, and watch enthusiast. He is the author of four novels. You can follow him on Instagram.

Off The Cuff articles are full-length, hands-on reviews of the watch in question and represent the opinion of the author only. All photos are original, unless specified otherwise. If you would like to have your watch reviewed on this site, contact us here.

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2 thoughts on “Other Watchy Bits: The Omega Speedmaster 125

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