Hi there! First time poster. I purchased a new Speedmaster Racing from my local AD about 3 weeks ago, ref number 326.30.40.50.03.001. I've been wearing it for the better part of those 3 weeks now, and I've been noticing that it is running about 5 seconds fast per day.

This watch is a chronometer and from what I understand they have a rated accuracy of -4/+6 seconds per day. Given that, I'm still a bit surprised that it is running 5 seconds fast, given that Omega is supposed to be in a higher class of watches.

Is this something that I should be concerned about? I should also note that this is my first experience with this class of automatic watches. I'm coming from a Citizen Eco-Drive but I know that watch is quartz and automatic watches typically can't match them in terms of timekeeping accuracy.

Thanks!

 

It's an excellent accuracy for a chronometer grade movement. Just relax and enjoy your watch.
You may experiment with your watch a little by keeping different sides up at night to see when it slows down at night so that you get an overall more accurate 24 results.
Welcome to our splendid forum.

 

Non chrono spec watches are plus +/15 or more depending on mfg.

Your in spec. Watches run slightly fast and slightly slow based on the position they are in due to gravity effects on the hair spring.

try leaving your watch in a different position over night and see what is the best one to dial in as close to 0 as possible.

+5 on a used watch with no service history even a chrono grade is not bad at all for any brand.

 

Thanks all for the info! I feel a lot more at ease now, especially given the cost of this thing. I'll definitely test out leaving it in different positions at night to see if it improves things.

It's actually a new watch. My local AD gave me the one they had in the back because I didn't want the display model. So it was probably sitting around unwound for who knows how long, which is why I wanted to wear it for a while first, in case there was a need for a break-in period.

 

Break in periods are a myth, and that watch has been sitting around for years, they have been out of production for 3 or 4 years at least if not 5 plus. Hence why I stated it was not a new watch. Its pretty much due for a service at this point.

 

If the watch is running +5 seconds per day now I don't think the OP should do anything right now, he can keep an eye on things and if they change he can address it at that point. He does have a five year warranty as a new watch. For now, wear it and enjoy it.

 

I think Omega tolerances for this type of movement are -1/+6 seconds per day, so +5 s/day is not out of specs. But it could be regulated to be closer to zero for your wearing habits, which I think is something rarely done today, but was apparently more common during the pocket watch era.
Also, search for one of Archer's posts for a clear explanation of how Omega's testing procedure might not exactly reproduce the rate seen on your wrist.

I would give it a bit more time, but I wouldn't expect the rate to change much if at all. From my experience with exactly one watch of this type, these movements are most amazingly stable. Over the last year, I have not seen any change with time, and my watch has insignificant variation in positions. It's running at +0.9s/day, with a variation of maybe +/- 0.2s/day for different measurement periods of several days.

If your watch stays at +5s/day, but is stable, and you don't see enough variation in positions to slow it down over night, I'm sure you could get it regulated closer to 0 s/day. The important thing would be to tell the person doing the adjustment (really, regulation, adjustment means something different) that you want it slower by X s/day; reason being they will measure a different rate on their bench from what you are seeing on your wrist, but the difference due to an adjustment should be the same. So if they make it 3 s/day slower, it should be 3 s/day slower for you, never mind whether they saw the same +5 s/day or +2 s/day or some other rate before doing the adjustment.

See also "https://www.omegawatches.com/en-us/customer-service/faq"
"
What are the precision tolerances for an OMEGA chronometer?
To earn the title of chronometer, the mechanical movement’s average daily variation in rate must be between -4/+6 seconds per day, or a precision of 99.99%, the highest precision attainable by a mechanical movement. The precision of a mechanical movement depends on the individual habits of the wearer and can therefore vary. A qualified OMEGA watchmaker can adjust the precision of a watch to within the OMEGA tolerances, which are from -1 to +6 seconds per day."

 

@Gruesome your confusing the new metas spec with chrono spec.
+-5 is correct for that watch.

 

Mhmm. I think I quoted the Omega FAQ directly. Do you read something different? It says -4/+6 for chronometers, and -1/+6 for Omega tolerances.

But regardless, the conclusion would still be the same.

 

Omega COSC rated watches (before co-axial even) were rated from -1 to +6 for average daily rates, so what you have stated is absolutely correct. Rolex goes on and on about accuracy, but Omega specs were tighter for many years...