Originally Posted by
volosong
Limited inventory at low volume dealers is frustrating, but something we will have to live with. One thing to remember about Trek, and I'm not sure it relates to the Domane line, but certainly does with the Madone line; is that the "size" that Trek lists has nothing to do with top tube length. My Madone is size 61, but all my other bikes are size 57.5 to 59. Those bikes actually have a high coorelation between top tube length and the model size. I have no idea why Trek does this. It's almost as worse as manufactures who only lists their bikes as S, M, L, and XL.
By the way, I took a Domane on an extended test ride and came oh so close to handing over my money. It is a sweet riding bicycle.
Well of course, citing ST length, e.g. 60cm, as a shorthand for sizing only ever worked because of the relative uniformity of traditional road bike geometry. Today, with such a wide range of geometries available, that old cheat doesn't work anymore, and I would argue, really hasn't in 20 years or so, only now it's glaringly obvious.
So what to do when, like Trek, you've got a frame that's not classic geometry? I think they decided to go the route of trying to make it easier for everyone to comprehend by saying this 60cm Domane frame, with its 56.7cm ST and 57.9 TT, "fits those who ride traditional 60cm frames."
Breezer, whose Venturi I ride, also have non-tradtional geometry, mine with a 54 ST with a 57 TT, which they call a Medum/Large.
Which is better? The basic problem is that there is no accurate shorthand for geometry, so any path represents it's own shortcomings, and we're saddled with a traditional reference system that is simply outmoded.