Lovely Mixte here and picture from:
https://rustybikebell.wordpress.com/category/mixte-bikes/ Buying a Vintage Mixte: What to Look For
I know that several of my readers are hunting for vintage mixtes at the moment - intending to use them as sportier alternatives to their main transport bikes. Early summer is a good time to buy a vintage mixte, as many are on the market. But before getting swept up in the romance of those twin lateral stays and buying the first attractive mixte you see, it could be helpful to know what to look for - lest you end up with a bicycle that is un-ridable at your skill level, or with a bicycle where you will have to replace so many parts that the purchase will not be worth it.
Let's start with geometry, and I will try not to make this too technical. It is tempting to look at a mixte and think of it as a cute, comfy "girly bike." But most mixtes from the 1970s and 1980s that you will find on the vintage market were designed as roadbikes. This means that they are not that comfy, and not that easy to ride. And this has nothing to do with whether the bike has drop bars vs swept-back handlebars, but rather with the bicycle's inherent geometry. Without measuring distances and angles, here are some ways to test whether a mixte was designed as a roadbike:
1. Steep Angles? Set the bicycle's saddle height to a level where your leg is extended fully or nearly fully on the downstroke. Are you at all able to touch the ground with one tip of a toe at this saddle height? If yes, or almost, then the bicycle was likely designed with comfortable angles. If not even close, then it was designed with steeper angles. While you can change the angle of the seat tube by moving the saddle backwards, a steep seat tube angle usually means that the bicycle is aggressive in other ways as well, which is what makes it an easy indicator of comfort. Steep angles tend to make a bicycle less comfortable - so take this into consideration.
Continued: http://lovelybike.blogspot.com/2010/06/buying-vintage-mixte-what-to-look-for.html
We don't have a mixte on hand, but we do have a woman's step-through bike, it sails, runs fine with indexed SIS shifting and is fairly nice, nothing exquisite. A guest bike, slightly on the small side but if I ever changed the handlebar stem to give more length to the bike, it might work out.
