A few weeks back, I posted this 1950s French-made Chrisfer as my WRUW of the day, having just had it serviced. It’s powered by an unprepossessing, but nowadays uncommon, 15j Lorsa 652 pin lever and I suddenly became aware that it was taking rather a long time to fully wind down.
R.R.’s archive attributes a power reserve of 37hrs to this movement, so I fully wound mine again and left it dial up on my desk, synching it with the atomic clock and taking a note of the start time. On the first trial, it ran for 52hrs 30mins with no visual loss of accuracy until inside the final few minutes, but not really believing my own eyes, I repeated the exercise. This time it ran for 52hrs 45mins, again with the same degree of accuracy.
Now, I usually expect something between the high twenties to the high thirties for my pin levers, but for this thing to seemingly out-perform all of my jewelled-lever movements by some margin is both remarkable and testament to what a 60-odd years old pin lever can still achieve. Just wanted to share this!