Finally broke down and purchased a grail watch of mine. The Yach-Master II in-depth.

[Spartan1]

Beautiful pics/review. Y-M II continues to sing to me. Lose the texted bezel and it’s one of my favs! Enjoy it, my friend!

[bradyb]

Such an amazing piece, and I've never seen one in the wild.

[EndlessEight]

Edit: disregard

[Mystro]

Update to its power reserve test.

I always like to do a initial power reserve test of a new watch. It can be very difficult because you can’t wear the watch for the test but because of our snow storm, I opted to do the test knowing I would be doing a lot of snow removal. Here are my notes of the test:

12/15/20 7pm full wound +0.0 resting 12UP
12/16/20 +1.0 @ 9:30am......+1.50 @ 3:45pm +2.0 @ 8:30pm
12/17/20 +2.0 @ 12:30pm.... +2.0 @ 7:30pm
12/18/20 -1.0 @ 9:30am. -4.0 @ 3:30pm. -6.0 @ 5:15pm. -9.0 @ 6:15
Stopped 6:46. 71 hours and 46 minutes

Rolex states 72 hours approximately for the caliber 4161 so I am right on spec. Now I have a base line for future test to gage the main springs health. What I found the most impressive with this movements test was how long the movement stayed well within COSC long into its mainspring wearing down. As most know accuracy is only measured at the top of its mainspring fully wound but after that initial 24h, amplitude will get lower and that will also change its accuracy. For this YMII, I am in Swiss COSC for 68 hours and “ Superlative Chronometer” for 60 hours which may be a record for any of my Rolex watches. :happyanim:

As a reference of some of the other new Rolex movements I have tested.
Rolex DSSD JC 126660 movement 3235 total:h70:05
Rolex SD43 126600 movement 3235 total: h70:23
Rolex CHNR 126711CHNR movement 3285 total: h71:44
Rolex BLNR 126810BLNR movement 3285 total: h72:40

To do this simple test: Wind the watch fully and set the time to a atomic clock. Set the watch down to where you can see the time but not have to touch the watch. Keep track of the watch daily until it stops. This will give you a mainspring check-up and reference point. Notice where in the power reserve you start to see the accuracy start to fall off.
Why this matters:
Now if you drop or notice issues with your watch, you can do this test again and compare if you may have any mainspring damage. If all of a sudden you are getting 17 hours power reserve, you know your mainspring has broken. Think of it as a EKG of your watch.

[Puppysmasher]

Stunning photos. Love the pairing with the PO. If I had the money (and wrist) the YM II in two tone rose gold has always been a favorite of mine.

I've always been surprised that the YM II isn't more popular. The general media always likes to complain that modern Rolex is too conservative, boring, and lacks innovation compared to the brand's past but YM II is such a unique piece and yet doesn't get enough love. Perhaps its the size or higher price tag that dissuades people from ever considering it.

[Random]

Mystro,

Thanks for such an amazing review and all the follow up information too. It has to be the best real world review of this mechanical masterpiece available anywhere and the pictures are truly at another level too.

This model has been calling for many years now - but I haven’t yet had the opportunity to yet try one on. I know it is badged as a 44mm but it does appear to wear quite compact from what I’ve read and your pictures. I understand the lug height is almost dead on 50mm but I have struggled to find any information regarding actual bezel diameter. I know from other models that this can sometimes be less than the stated case diameter. Could you maybe measure the actual bezel diameter? Grateful for any more info, weight etc., and do please add more pictures to this most comprehensive “reference” review of yours.

Thanks and all the best,

Random

[Mystro]

Originally Posted by Random

Mystro,

Thanks for such an amazing review and all the follow up information too. It has to be the best real world review of this mechanical masterpiece available anywhere and the pictures are truly at another level too.

This model has been calling for many years now - but I haven’t yet had the opportunity to yet try one on. I know it is badged as a 44mm but it does appear to wear quite compact from what I’ve read and your pictures. I understand the lug height is almost dead on 50mm but I have struggled to find any information regarding actual bezel diameter. I know from other models that this can sometimes be less than the stated case diameter. Could you maybe measure the actual bezel diameter? Grateful for any more info, weight etc., and do please add more pictures to this most comprehensive “reference” review of yours.

Thanks and all the best,

Random

I will do some measurements when I get a chance. The daily comfort of this watch really feels like a 40mm Sub. It is because the case is so thin and spreads it’s weight out over a large case back. The case is also designed to flow better through it’s turned down lugs and nothing like a super case.

[Random]

Hey Mystro.

thanks and no hurry either!! Another superb picture too. Amazing side shot

Best, Random

[Mystro]

Originally Posted by Random

Hey Mystro.

thanks and no hurry either!! Another superb picture too. Amazing side shot

Best, Random

My calipers are at my office somewhere and I will have to find them next time I go in. Between Covid and home schooling my kids I have been consulting from my home office.

[ReinoudLouman]

what an exclusive watch :o