5002 TRANSITIONAL

Hi,  I have a question I currently own a Big Pilot Transitional 5002 and a 5004 and I have noticed that the 5004 has a thicker case than the 5002. Does anyone know the exact thickness? When I look at the online info it states that they are both 15.8mm thick but the 5002 seems thinner. I also had my 5002 serviced through IWC and they are not aware of a Transitional model, I found that a bit weird. Does anyone have any info on these transitional models? 

The original 5002 had a frequency of 18'000 half beats per hour which is 2.5 Hz. That was the frequency of a pocket watch movement. The caliber 5000 was developed with that specification. It was a movement with 7 (8) days of power reserve.

It turned out a bit tough to regulate properly so there were some technical adjustments to the movement concerning the balance spring. The frequency was changed to 21'600 (3 Hz). The rest of the watch stayed unmodified. I think that was the transitional version. 

Later the movement was changed to 4 Hz and the ref # changed as well. The case to my knowledge stayed the same.

Please correct me or add some missing details if I'm wrong or left out some important information.

I checked the books and correct my statement former statement a bit.

The Ref 5002 movement was changed to 3 Hz frequency. These are the Transitional models.

Reference       Caliber     Freqency    Year     Info

5002                 50110       2.5 Hz         2002     1. version

5002                 51110       3.0 Hz         2005     Transitional

5004                 51110       3.0 Hz         2006      

5004                 51111       3.0 Hz         2008      

In 2006 the whole layout of the watch and dial changed to Ref. 5004. The movement frequency stayed at 3 Hz.

The 5002 high beat “Transitional” watches that I have seen are never lower than serial number 314#### and I have not seen one higher than 316####. That being said, I have seen many 5002s listed for sale as “Transitional” models that are actually standard low beat 5002s with service-replaced probus crowns so I think there is some confusion in the general marketplace regarding the “Transitional” designation. One thing that I have wondered about is whether any platinum “Transitional” 5002s exist.