Doesn't matter which bike for saddle fit- they are all the same. Height and fore and aft position in relationship to the pedals is the same. On the 3 road bikes- I have two different crank lengths- but that saddle position is still the same.
Then there is reach to the bars. The road bikes from the sit part of the saddle to the centre of the bars are all within 5 mm of each other. Different top tube lengths- but different length stems to accomodate them
But Bar height-- Vastly different. The OCR and the bars are level with the saddle. The TCR and bars are 2" below the saddle and Boreas is 3" difference. I do not feel any difference between the TCR and Boreas other than after about 60 miles and I find that Boreas may require me to start riding on the top of the bars a bit more to ease the backache. I rarely ride the OCR as I keep that as a loaner bike but to me that bike is not as good a ride as it used to be.
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How long was I in the army? Five foot seven.
Spike Milligan