I had the opportunity to time my watches recently and thought it would be good to compare the performance of a 15 year old NOS Seiko 4s against an officially serviced Credor 4s from the same period.
I have mentioned about my servicing experience here, but this is the first time I have an objective look at the results. The servicing was done by Seiko in Japan.
The NOS sample is the Laurel reissue from the Seiko Historical Collection the Year 2000, SCVM001.
I also chose these 2 because they have similar movements with the Credor having an additional power reserve complication, 4s79 vs 4s28. Otherwise both are handwinding only with small seconds, beating at 8bps.
Serviced Credor (dial up and assume 52 degree lift angle)
250 degree amplitude
0.1ms beat error
NOS laurel Reissue (dial up and assume 52 degree lift angle)
290 degree amplitude
0.1ms beat error
It is better to have NOS watches than send them in for authorised servicing, especially where watch performance is concerned. In my Credor’s case, apparently they didn’t feel the need to replace any parts and can accept the amplitude. Should the mainspring be replaced, amplitude should increase slightly, but no guarantees. In fact, given wear and tear, I’m not certain if it can still hit the high 200s short of replacing all the important moving parts, for which Seiko no longer produces.
Another conclusion I can draw is that unlike vintage watches, contemporary watches really do stay like new if you do not use them. I’m frankly quite astonished by the amplitude reading on the 15 year old NOS Laurel given that Seikos are well known for their lower amplitude. 300 degree is great even by Swiss standards.
Please take note that my conclusions are drawn from only 2 samples from my personal collection and should NOT be regarded as being representative of serviced nor NOS watches in general!