AP caliber 7121/5900 technical specifications

[Crazywis]

Does anyone have access to technical information on AP calibers? I'm interested in finding out the moment of inertia numbers of the balance wheel on calibers 7121, 5900 and 3120 but it appears that AP doesn't directly disclose this information. FPJ and RM are forthcoming with this info and include it as a part of their usual caliber specs. PP included this info in the marketing material at the launch of ref 6119 for cal 30-255 PS but appear to be tight lipped otherwise.

For anyone interested, I came across this article which does an excellent job of doing a simple first order analysis of predicted chronometric performance (on the wrist) of many movements produced on an assembly line and begins to provide insight into one of the challenges of building small, slim movements and the potential benefits of individually adjusting and tuning them - https://watchesbysjx.com/2020/12/qua...esign-hdf.html

[IGY]

I've been reading the same articles from SJX (an excellent resource) and I've just been going down the same rabbit hole as regards the AP 5900. This newish movement is larger diameter than the preceding AP 5800, which was a modified Vaucher VMF 3002. So while data is readily available for the VMF 3002 I have not been able to find out any information about the AP 5900.

The sales "experts" at my AP House are predictably clueless. They "ohh" and "ahh" about the colours of the dials and all the tasteless blingy materials on the special editions, but all they can say in answer to questions about the movements is that "you clearly know a lot more about this than me." Yeah? No kidding.

I've also been looking at the 4131 fitted to the 2023 Daytona. This has the Chronergy escape wheel and spring barrels added beyond the UV-LIGA chronometer seconds wheel fitted to the 4130. So it really looks like a very nice to have upgrade to the Q-factor / power efficiency. I'd love to see that added to those charts provided by SJX.