Some time ago, Bas van Dorp and I both decided we needed a Lemania 5100 watch. I bought a Sinn 142 St.S at Horloge Platform Nederland in The Hague and Bas ordered a Sinn EZM1. His one was on order, and since the run on the last watches with Lemania 5100 was enormous, he had to wait a bit longer. Last week his watch arrived and here you can read his review on his EZM1.

About two years ago, I read that Lemania would end the production of the
cal. 5100. The horror! The guys who came up with this idea will be the
first against the wall when the revolution comes, that's for sure. Sinn,
among others, would still be producing watches with this movement, using
the remaining stock. I was still happy wearing my Omega Speedmaster
Professional (which has a Lemania 1873), and there was still some time
to decide. However, recently, Sinn has also stopped the production of
5100 based watches, so I quickly decided to order one of the last EZM
1's. I received it 5 days ago...

I like functional designs. The reason I got a Speedmaster Pro was
because it has the best designed chronograph dial ever. Extremely good
to read, beautiful and timeless design. The Sinn EZM 1 shares many of
these features, but in a very different way. But most of all: both
watches make a statement on watch design.

The Sinn has no subdials but it still has a two register chronograph.
That's one of the odd features of the Lemania 5100, it has a central
seconds and a central minutes register. Additional to these four central
hands, the Lemania 5100 allows for three subdials (24 hour hand, normal
seconds hand and chrono hour totalizer), but Sinn didn't use them in the
EZM 1. Who needs these functions anyway? Sinn considers extreme
legibility more important, so let's throw these registers away, even
though we payed for them. A very bold statement.

Both Sinn and Omega considered legibility the most important goal but
they defined their design constraints different. I found the Sinn's
overall legibility better in the dark and I found it is particularly
easier to read the chronograph in the dark. The Omega, however, allows
more accurate and easier reading of the seconds counter in normal
conditions, because of it's "perfect" outer scale where every second has
an identical, very thin marker (now that's a statement). The Sinn
doesn't have this, the markers on the hours are thicker it doesn't even
have a marker on 1 and 59 seconds because of the huge 12 hour marker.
You can still use the chrono, but not to the degree of perfection in the
Speedmaster. I'd say for scientific purposes the Omega is better, but
for the rough work "in the field", the Sinn is better. For timing pasta,
both watches will do just fine. But wait! The Sinn has a rotating bezel
which gives you a countown timer for the pasta so you can use still the
chrono to time the desert in the oven. The date window is a nice bonus,
and Sinn did a perfect job not to make the date window interfere with
the legibility of the rest of the watch. Also a bold statement.

The Sinn looks much more modern, not as timeless as the Speedmaster. But
I do consider the Sinn EZM 1 a classic. Time will tell if I'm right.
Where the Speedmaster Pro looks like a technical instrument, the EZM has
the appearance of a hefty diver's watch, a bit like the IWC Aquatimer,
Omega Seamaster 300 and Rolex Submariner. However, Sinn took the "form
follows function" adagium to a new level. The date indicator is in red
and even the brand and model names are in red. Oh by the way, the model
name, "Einsatzzeitmesser" might be the main reason for me to get this
watch (I like long German words that just say it all).

I have to mention the crown & pushers on the left side (great, all
automatic watches should have this), copper sulphate capsule (great idea
if you ask me), the German lettering on the back, the superbly designed
hands, the clear manual, the not-so-pretty-but-comfortable bracelet, and
the beautiful straps.

I consider the 142, the 157 and the EZM 1 the best designed watches in
the Sinn catalogue so I sincerely hope that Sinn can come up with
replacements for all these great 5100 based watches that are out of
production now. The 656 and 756 lines surely look promising. In the
meanwhile, when people ask: "how much does your watch cost?", I reply:
"that doesn't matter, it's not in production anymore."
  • Chuck Maddox

    Bas says: “The guys who came up with this idea will be the first against the wall when the revolution comes, that’s for sure.”

    Let me be the first person to volunteer for the duty of being on the firing squad(s)… I’ll even supply my own firearm and ammunition! I’m thinking the Browning Auto-5 12-gauge with 3″ magnum deer slugs would be my first choice. Weatherby .460 Weatherby Magnum would be 2nd… The Weatherby has a ton more muzzle pressure and velosity, but the 12-gauge has a bigger shell.

    I eagarly look forward to this duty!

    — Chuck

  • Nivelacuso

    Good review. I’m also awaiting a EZM1.

    Perhaps Poljot can buy the tools and machinery from Lemania for producing the a russian version of the Lemania 5100…. Such a pity to see this movement discontinued.

    Hans Mennink

  • Bas

    I forgot to mention that I “borrowed” the “will be the first against the wall when the revolution comes” part from “The Hitchhiker’s Guide to the Galaxy”, by Douglas Adams. In the book, “The Guide” says this about the marketing division of some large company. Go figure…

  • The L5100 isn’t discontinued if you belong to the Swatch group ;^P

  • 2112, can you expand on: “The L5100 isn‚Äôt discontinued if you belong to the Swatch group”?

    So it will still be ijn production for Swatch companies? May I ask where you heard/read this? Just curious.


  • Bas

    Ironically, my EZM.1 stopped last night 🙁 It seems an automatic winding problem. I don’t really worry as I’m quite confident that Horlogeplatform Den Haag (my watch pusher) will have it fixed by Sinn. But it’s still a crack in the Lemania 5100 legend… At the moment, my ultra-reliable Speedmaster is back on my wrist 🙂

    Bas van Dorp

  • Jeremy O’Kelly


    I don’t know that ‘fixing’ it is an issue. This is a peculiarity that crops up in a number of EZM-1’s. Some have a low power reserve, some don’t. Check the Sinn forum archive, and you’ll see many other people with this phenomenon. Winders or vigorus wear seem to be one solution.

    Oddly, it ONLY appears with the EZM-1 and none of their other 5100 models (156, 142, etc.) Some suspect that it has to do with a winding rotor modification.


    Jeremy O’Kelly

  • Jeremy O’Kelly


    The movement is owned by Swatch, and they have chosen to discontinue it. There has been some indication that they could choose in the future to use it in one of their own lines – but for competitors it is no more.



  • Bas

    Jeremy, thanks for your comments. The fact that it happens often gives me good hope that Sinn will be able to pin down the problem.

    Jeremy wrote: “Winders or vigorus wear seem to be one solution.

    No thanks 🙂 I will not buy a winder as a workaround for a broken watch, nor will I wear my watch vigorously. That’s just ridiculous.

    I have an 1969 Omega (cal 564) that just sucks energy from thin air. 4 hours of normal wear gives it 45 hours of power reserve.

    Having seen this, I think that in 2004, a company like Sinn should be able to make an automatic watch that makes it through the night, period.

    Disclaimer: I’ve only done one winding efficiency measurement ever on my Omega 564, but I will wear the EZM1 and the 564 together for 4 hours and then compare the reserve they collected.

  • georges

    very sad that the 5100 is discontinued:(.It was an excellent movement way better than the valjoux 7750 and all its derivatives. RIP Lemania 5100, gone but never forgotten.

  • Todd Crawford

    I just got an EZM1 too – I was worried that they would be gone and I would always regret not buying one. So far, so good. It keeps great time and seems to have a normal power reserve.

    I consider it the Heckler & Koch of watches. Hey, if it is good enough for the German Special Forces, it is good enough for me.

    Here is another article on the EZM1 –

  • Bas

    Hmm, I just read this back, seems some update is needed even though it is rather late. The watch was sent back to Sinn and I remember it took them some weeks to fix it… I was told that the winding stem was too long, which locks the winding mechanism when you screw the crown. This did sound a bit weird to me but the watch didn’t show any power reserve problems ever since, it Just Works now.