Types Of Movements In Daytonas

[kingkitesurf]

I am confused on the movements in Daytonas... There are Lemania manual chronos, Asian 7750, nwe gen Asian 7750 (which are according to Zigs better but still unreliable) and there are Swiss Valjoux 7750. Who has experience with these different movements on the long run (let's say 6 months)... Is the Lemania the most reliable with the only drawback to be manual? I am looking for an daily wearable nice timekeeper... and not a cabinet showoff. Usability comes first...

Any advise

[slay]

yes, the lemania (venus) is the most reliable, but it has the wrong subdial spacing and does not have an hour counter

[zbig]

I have daytona with 7750B1 no problem so far. Used 10 months.

[archibald]

I am confused on the movements in Daytonas... There are Lemania manual chronos, Asian 7750, nwe gen Asian 7750 (which are according to Zigs better but still unreliable) and there are Swiss Valjoux 7750. Who has experience with these different movements on the long run (let's say 6 months)... Is the Lemania the most reliable with the only drawback to be manual? I am looking for an daily wearable nice timekeeper... and not a cabinet showoff. Usability comes first...

Any advise

Id usability comes first, do you absolutely need a daytona? There are dozens of chronograph reps that will give you the reliability of the swiss 7750 or Venus 175 Copy without sacrificing accuracy. People suffer through the crappy movements on their daytonas because all of the watches powered by reliable movements can be spotted as fakes in 1/2 of a second.

Pardner, I've been there...you fall in love w/ a gen and you absolutely need the rep, so you sacrifice reliability and accuracy. And then someone says..."nice fake" or the movement stops working after 3 days. Do yourself a favor, buy a navitimer or PAM 196 and start saving up for an el-primero based frankentona...you'll be a lot happier in the long run.

[ubiquitous]

Okay... For Daytona reps, you have several different choices that are model specific. I'll try to outline the more popular ones for you.

Vintage 6263/6265 Daytonas

The 6239/6240/6241/6263/6265's are the very first actual Cosmographs known as Daytonas. The 6238, which preceded the 6239 was a 'Pre-Daytona', as it was not a Cosmograph; i.e. the tachyring was not on the bezel, but on the outer edge of the dial. These models are handwind and came with Valjoux 72 movements reworked by Rolex into the caliber 727. These watches were produced from 1960 until 1987.

There are several replicas of this watch- All of which carry their own characteristics. I will cover them here:

DW- DW stands for David Wong, a very low profile yet legendary dealer who is best known for his DW 6263/5's. These watches are the best of the vintage Daytonas as they carry all the correct case dimensions- 37.Xmm case, 19mm lugs, asymmtric pushers, and like MBW vintage watches, they accept genuine parts. There are several variations of DW's, all of which have to do with the type of movement contained within:

-V23 copy

-V72 (case kits only)

-7750 (asian)

The V23 copy mimics the V72 very well in appearance. Subdial spacing is correct, and these will even accept a genuine dial. As the V23 is a bi-compax movement, the hour counter is not functional, but the hand is frozen in place (so, if you're like me and never use the stopwatch anyways, it's no big deal). The 7750 Asian is the same typically found in most other 7750 B1/Asian watches. Subdial spacing is not as correct, and the movement is also an automatic (where it should be a manual wind). This, however is easily remedied as the movement can be converted to handwind. This is also the same watch that was offered on TRC a year or two ago (known as the ExtraExtra model, or EE for short). The V72 case kit gets honorable mention here as the basis for a great frankenstein project. Just get one of DW's case kits, add your own V72 movement, and you have one exceptionally nice 6263/5 replica.

Venus based- These 6263's come fitted with the so-called Lemania movement (it's actually a Venus copy by Sea-Gull). The characteristics for these models are- 37mm to 40mm case size, 20mm lugs, symmetric pushers, incorrect subdial spacing. Like the DW V23 copy movement, the Venus movement also has a non-functional hour counter at 6:00; in it's place is a hand that follows the hour hand as I believe it is driven off of the same gear. The typical fix for this is to 'freeze' the hour hand, similar to the DW.

7750 based- These watches, as mentioned prior, have the >ahem< ubiquitous Asian 7750 movement inside. Some of these watches carry correct case characteristics (i.e. the DW) and some carry incorrect dimensions, like 40mm case diameters, 20mm lugs, and so on. Because these watches carry the 7750, they require an extra tall caseback to accomodate the rotor of the movement. This makes for a very tall, bulky case whereas the genuine 6263 is rather slim in profile.

Neo-Vintage 1652x Daytonas (Zenith)

The 1652x Daytonas were the models to supercede the vintage 626x models in 1988. These new Daytonas came equipped with the Zenith El Primero reworked by Rolex to become the caliber 4030. The new automatic movement was downshifted from 36.600bph to 28.800bph and was fitted to improve upon the cumbersome hand-wound Valjoux in the 'old' Daytona (the handwinding movement and screwdown crown of that model made it very unpopular as it was not very practical).

There are a number of replications of this watch that exist- Many cheap quartz and Day-Date functioning models which I won't get into. The majority of the 'quality' replicas that exist carry the Asian 7750 movement. As the Asian 7750 (technically, I'd say this should be termed as a 7753 due to the subdial layout) carries the running seconds at 9:00, this movement best mimics the El Primer's in function. However, as far as aesthetics go, this movement is far from accurate, as the El Primero carries a very unique subdial positioning (all the registers are grouped closely together, as evidenced in my photo above). So, it is easy to spot a 7750 based replica because the spacing of the subdials is spread too far apart on these models.

Now, you can build a frankenstein like I have chosen to do. This requires time, ability, tools, and most importantly, money as the parts involved are not cheap. The project entails using a case made specifically for the EP 400 (or a genuine case), genuine dial, hands, crown, tube, and a Zenith El Primero 400 movement. Add them all together, and you have essentially the same watch as genuine, yet without the beat downshift and provenance of a genuine. In terms of function and aesthetics... This watch is the same at a fraction of the cost of a pre-owned genuine on the secondary market.

Moving right along....

Modern 1165xx Daytonas

The modern 116520/3/8/509/519 Daytonas, introduced in 2000, now carry an in-house Rolex developed and manufactured 4130 movement. This movement, completely unique to any prior Daytona movements previously offered carries the running seconds at 6:00, and has a number of improvements to it over the El Primero 400 in terms of function, and servicability. Aestehtically, the biggest difference with this model Daytona and it's predecessor are 1) subdial positioning. Because the stopwatch reset lever now resides below the 6:00 counter, all of the subdial registers had to be shifted up towards 12:00. This means that the registers at 9:00 and 3:00 (hour and 30 minute counter) now sit slightly above axis to the hour/minute and center seconds hands and 2) the subdials are now ringed with silver, instead of the contrasting black or off-white rings of the 16520.

With regards to replications, there are a few different flavors out there that exist, but most of which are based on the Asian 7750. To start, there's the plain jane, run of the mill Asian 7750, which carries incorrect subdial spacing for this model, as well as running seconds at the incorrect 9:00 position.

Then of course, there's the mod-7750, which is either a Swiss or Asian 7750 modified with 11 extra gears and additional bridges to replicate the appearance and function of the genuine 4130. There are, in my opinion, 2 major drawbacks to this movement: reliability, and size. Because the modification is adding 11 extra gears, there is much more strain on the movement than ever originally intended. As the movement was never engineered for such demands, as well as the fact that the movements don't arrive well oiled as evidenced by our resident movement guru Ziggy, it's not hard to see that the movements in these are not likely to live long lives (though your mileage may vary). As for size... This movement is simply too thick. Those added gears and bridges add height to the profile of the movement- Specifically at the dial side. Since extra height is added, this mucks up the proportions of the casing as the profile of the caseband is too thick, the casebacks are too tall, and in most cases, the bezel and rehaut are too tall/deep, or if they are of correct size, the backspacing is offset by sinking the crown into the crownguard towards the back of the case (resulting in a really ugly gap between the crown and the bezel).

Well... I think that about covers it. Please excuse any spelling or gramatical errors (I still have not had my morning coffee yet)...

Best!

R

[kingkitesurf]

Djeeeeeez Ubi....

I have been researching all posts with Daytona, El Primero, Paul Newman etc etc. This was two evenings of reading.... Info overloaded completely.

Now you just sum it all up and I finally think I understand...

Is your middle name God or something....

Great informative posts.... I am not worthy.... I am not worthy

[vlaletom]

Great post ubi

You must have taken your time on this one.

it will really help out anybody willing to pick up a daytona.

[Linder]

Yes, it needs to be moved to the Knowledge Base under its own thread.

[Guest avitt]

Fantastic summary!

[ubiquitous]

Thanks guys...

[sonystyle]

Thats really was a great post, actually I wanted to ask something similar, but with all the jokes on "who has the best sub" I was kind of afraid to ask

Copy->Paste into notepad and save as DaytonaRepMovt.txt

Very valuable post, it should either be a sticky, post of the month, or archive for sure !

[RWG Technical]

Well that was one of the best posts I have seen in a long time... I know nothing about these models, and I have cut and pasted this information and printed it for my reference. It's going to go in my watch information binder...

Thanks for this, much appreciated.

RG

[Le-LibanoMarseillais]

i have a daytona 7750 asian ! and it is the worst movement i ever had ! no luck for me but the watch itself is a must have !!

if you have the money then go for a swiss movement daytona and NOT the asian one !

it drives me crazy to have to fix the time on my watch 3 times per day !

[r11co]

if you have the money then go for a swiss movement daytona and NOT the asian one !

I have to disagree. There is little benefit in paying the considerable premium for a Swiss based movement as the transfer gears used to replicate the Rolex layout are still aftermarket and still produce a movement that is too thick, and a disproportionate watch is the result. A little extra reliability for a lot of money doesn't disguise an expensive watch that still screams REP!!

It is about time people just accepted that any 7750 based Daytona, regardless of layout, is going to be a poor compromise.

I wish people would just stop buying them as it might encourage the development of a decent El Primero rep movement, and think of the possibilities that would open up....

(thinks TAG Calibre 36, Monza, Planet Ocean Chrono..........)

Edited September 7, 2006 by r11co

[Guest avitt]

There no doubt that, if you have the will, the skill, and the funds, the best options are the Valjoux and El Primero based frankens. There is nothing like having a movement that is essentially the same as the original.

[ubiquitous]

Agree 100%! Having the right movement in the case is a beautiful thing

[manuel]

I wish people would just stop buying them as it might encourage the development of a decent El Primero rep movement, and think of the possibilities that would open up....

(thinks TAG Calibre 36, Monza, Planet Ocean Chrono..........)

Well said!

Ubiquitous: Very nice and informative post.

I alredy knew all that stuff because I spend a lot of time reading your posts, but this is a very good and important compilation. Thanks

[TwoTone]

Topic moved to Knowledge Base and Pinned...

TT

[panerai-ss]

Thank you so much for a great detail write up. It is really a knowledge base thread. I do really appreicate for all the information and data which help me to make decision on Rolex Daytona.

[UB7]

I have 3 daytonas, 2 with the modded 7750 and have had no problems so far, 1 of them is relatively new and the other ive had for close to 6 months and it varies within +/- 4 seconds which is pretty dam good. Excellent write up on the movements, hats off~

Edited October 7, 2007 by UB7

[mag1119]

Excellent post, ubi.! I own several Daytonas and between your post and By-Tor's post about these pieces the topic was covered both mechanically and cosmetically, many thanks. I have gathered a lot of the info presented, but not in as concise a form as this.