Kommisar89

I guess I just assumed that mixte frames were measured the same as a standard diamond frame with just the diagonal bar instead of the standard top tube but now that I have one here and a standard frame of the essentially the same design to compare (PH18 and UO8) I can see they did some weird stuff. My wife's PH18 purports to be a 50cm bike. The seat tube does in fact measure 50cm CTC but much like modern sloping top tube bikes the head tube is higher than the top of the seat tube. If you draw an imaginary horizontal line from the point on the head tube where a standard top tube would attach to where it would intersect with the seat tube and measure to that point, the way you would measure a standard frame, it measures around 54cm (hard to get an exact measurement with all that imagining ). And sitting it next to my UO8, the bottom bracket, seat tube, and head tube line up exactly giving it the same 57cm effective top tube length.

So, my guess is that this frame is really built to the same measurements as a 54cm frame rather than a 50cm and that all of the Peugeot P8 series bikes use the same top tube length. One thing I find a bit odd about it is the way it handles with those porteur style bars - it feels quite different from the UO8 despite having the same geometry (in fact it feels a lot like my UO8 felt years ago when it was set up with North Road bars), sort of wiggly as there is very little weight on the front end to dampen the steering. Even a straight bar mountain bike puts you in a slight forward lean and your hands in front of the steering axis but these upright bars take all of your weight off the front end and put your hands behind the steering axis. And when I have to make a sharp turn such as a U-turn in the middle of the street, the bars hit my knees, forcing me to assume an awkward knee out position. Just feels really strange to me.

wrk101

FWIW: The three mixtes I have had in the last year: a Raleigh, a Panasonic, and a Centurion, all had conventional drop bars.

Kommisar89

I would imagine those handle basically the same as a standard bike with drop bars.

robatsu

My strictly ad-hoc impression of 70's/80's mixtes is that they tended to have a relatively short effective top tube length. Similarly unsupported by nothing other than conjecture is that these bikes were aimed at females who were thought to have relatively short torsos in relation to inseam when compared with males.

Whether any of this is true and the reasons supportable by solid factual evidence is left for other posters. But I do know that my experiments with vintabe mixtes has often left me feeling prone to knee knocking on the handlebars unless there is significant stem extension.

custermustache

I just set up my wife's mixte as a cruiser. Works great.

Kommisar89

Well since I'm 5'10" and my wife is 5'7" and we both have a 30" inseam I'd say that works pretty well for us. It could be (maybe, possiblly) that the knee knocking issue is because I have the seat jacked up to it's maximum extension and I'm hunched over the bars like a circus bear. Although my wife has the same inseam as me her feet are much smaller and she rides flat footed anyway while I ride toes down so her seat height will probably end up a good three inches below mine and her legs might clear the bars. I'm not even sure how to determine proper reach on this thing since the effective top tube is the same 57cm as my 22" frame Peugeot UO8 but with the current short stem and the porteur bars it puts the hand position a good 6 inches farther back. She'll probably like that as I think she likes the upright riding position.

Bionicycle

My 85 Fuji Sagres Mixte is a 191/2 frame; by the length from the BB to top of seat post. I’m 5’11 to 6’ depending on which shoes I’m wearing, with about a 30” inseam, so I have a fairly long torso. Before I developed my hip problems (main reason for the Mixte) I used to ride a rather large Schwinn Le Tour that was actually sized for someone 6’6”. I know this because he was a friend that I had bought it from, and he had bought it brand new in around 1976-77. It felt great top tube reach wise for me, but the stand over height was a bit (painfully) tall at time of quick stops.

Long story short when I bought my Mixte it had drop bars on it, and I thought “191/2” inch frame I’m going to be able look down in front of the front tire when I ride this thing”. Much to my surprise it felt very similar to the same reach as the Le Tour did. I was quite stretched out when in the drops. As I’m older now and less a fan of riding around in an aero position all the time I switched out the handle bars for set of North Road style and now set almost straight up quite comfortably.

My point is I don’t know if the original Cross Frame Mixte design was meant from the start as just a new frame idea, that seemed to become more popular with women, so evolved into women’s size frames, or as a Unisex frame (as I believe) that just never seemed to catch on with men. But, I have noticed a vast difference in size relation with different manufactures when it comes to seat tube length versus imaginary top tube length on Mixtes. Also, Mixte frames are a critter all there own, because my wife has a Schwinn Sprint 22” women’s frame, and the imaginary top tube length on it (as close as I can measure) is nearly three inches shorter than my Mixte, while the seat post in nearly two inches longer; and when I take it for a ride even with the drop bars still on it: it feel way more cramped than the Mixte did with drops.

So I think Mixte frames are just a strange thing to try and size in the conventional way, due to the fact that every company that made them seems to have tried to make them a little different from everyone else. If you ride it and it feels comfortable, chances are it’s a pretty close size for you.