daka

I had one of the short, steep all-white PX10LEs from the mid-seventies. Acceleration? Yes. Good climber? Yes. A bike you can ride all day? Big no. Brutally harsh ride and steering required "concentration".

Andy Antipas 

I'm not an expert on these frames. My interest in this frame is to see how the ride and handling compare to my British, Italian, American, and other French brands from approximately the same time period.
I believe Peugeot called this a 21 inch frame. The seat tube measures approximately 52cm CTC. Top tube is approximately 55cm CTC. Seat tube angle is about 75 degrees. Front center is 57.5cm.
The restoration of this PX-10 frame has been moving slowly for a variety of reasons, but if it keeps snowing I might have the bike assembled this weekend!

mikestr

Lookin' good! I think someone (Dave/ddd?) was waiting to see a smaller PX10 frame from this period, and yours looks like it. And it has an extra-long top tube and steep seat tube, like the 54x57 frames noted here. Have you estimated the head tube angle? 75-ish?

mikestr

I can confirm a similar front-center length on my 1974 54x57, about 57.7 cm. This would be typical on racing bikes of the 70s-80s, judging from the several I own. How Peugeot got there in this case, with a long TT and steep ST and HT angles, seems unusual for a production bike, but I'm no authority on this.

3alarmer 

...this was the reason behind my decision to equip my example with 27" wheels and wider tires than I often use. The increasing wheel and tire diameter increases trail. I think it worked a little bit, at least, to make the bicycle more forgiving in the longer ride department. But I never rode it with 700's, so it might be an imaginary gain.

BluePx10

More data: Just measured my ‘71 and ‘78. Frames have identical geometry. Both have parallel 73.5 angles, which I think signifies LE models. Seat tube: 21” (@53 cm) c-t. Top tube: 55cm c-c. Front center: 584mm.

mikestr

I wonder if customers complained about the ride of the '72-'75 models and Peugeot decided to return to the mellower geometry in response.

dddd

The LE bikes had 75+ degree frame angles in all but perhaps the smallest frame size(s) offered.
The 73.5-degree angles would be from the late-70's period following the mid-70's Thevenet/LE period.
I've never known exactly when this later geometry change occurred. I'd thought perhaps 1979 (since that was the year that the UO8/9/10 models got revised lugs, 103 Carbolite tubing and all-new geometry featuring a steeper seat tube but slacker head tube).

And Andy's 52x55cm, refinished frame is way interesting in that it likely has a slacker head tube angle to suit the shorter (55 vs 57cm) tt of the larger LE frames.
Without a slacker head tube angle, the rider's toe would contact the front tire solidly whenever the steering moved much off center.
This was the data point I was looking for.
Andy, can you measure your frame angles at some point?

daka

I'm surprised you could get 27s in there. I thought it had little room left with the 23mm wide tubulars mine had.

Andy Antipas 

According to my incredibly precise Harbor Freight digital gauge the seat tube angle measures 75.6 degrees and the head tube 76.2, which are pretty steep. It will be interesting to see how this bike rides.

Most of my classic racing bicycles have toe clip overlap. It is something I have dealt with throughout my years of riding and racing. I don't see it as a problem as long as one is aware of it.

dddd

I was perhaps confusing your post with BluePX10's post, but your 55cm top tube actually exists together with the steep angles.
Not too surprising as the steeper seat tube extends the front-center dimension, improving toe clearance.

So Peugeot's designers actually wanted the 57cm top tube length on their 54cm frames, sounds long but it is what it is.

And your 53cm frame has a full 2cm-shorter top tube. I'm assuming you measured from center to top on the seat tube length, i.e. frame size?

One of my best frames is a Nobilette with 74-degree angles, a 56cm top tube and yes, significant toe overlap. It's a great frame, even for longer rides, plenty of reach too with a 125mm stem.
I assume it's a custom, but fits my longer-legged body perfectly for spirited riding. I bought it for I think only $180 with haggard paint and a cracked right crankarm.

3alarmer 

...I probably wouldn't have tried it, until I saw that catalog picture of the UX-10 that showed me it was possible.

mikestr

dddd wrote, "The LE bikes had 75+ degree frame angles in all but perhaps the smallest frame size(s) offered."

I had thought that someone (you?) had stated that the LE and E frames had the same geometry. What is known about this? They were different frames: They had different lugs, for instance. But is that all?

mikestr

dddd wrote, "So Peugeot's designers actually wanted the 57cm top tube length on their 54cm frames, sounds long but it is what it is."

My best guess is ​​​​​​that they wanted the steep seat tube angle to place the rider farther forward and the steeper head tune and shallow fork rake for quick handling, and they wanted a consistent center-front length, so the long TT was simply a consequence.

The larger question is why they did this for a few years and then reverted more or less to previous geometry.

3alarmer 

https://www.bikeforums.net/23185789-post606.html

mikestr

I thought I had answered this but now can't see my reply. What you are pointing to in the photo is the edge of the clear plastic of the sticker, not any sort of crack. If you look closely you can see the paint scratches abruptly stop at that line and become visible again as they continue on the printed foil portion. Thanks for looking out for me ...

repechage

To my eyes, that is a true aluminum foil adhesive backed sticker, one can see the foil distortion at the point of the lug, and peeling / tearing on the RH side and aft portion of it below the rear brake cable.
I placed an arrow at what is probably the right hand end of the paint crack, arrowhead right at the terminus. I do not see any clear plastic. There is scratched paint in front and behind the foil, curious but it will remain so with the label remaining in position.

mikestr

What is the matter with you? I'm here; you're not. If you were here you could run your fingernail over that film and feel its slickness, see its gloss, feel its edge. I am not pulling it up for your benefit.

mikestr

Here is another view. You can see what it is: remnant of a now yellowed film backing of some sort. You can even see where a part of it is chipped away, so the edge is discontinuous. I don't know why the sticker was made that way; perhaps there was more to the foil section that came off or was removed at some point. The bike is 50 years old, man.

repechage

Foil on the bottom, 4 colors and a clear above. The white might be the top layer. Pretty impressive.
That transverse paint upset appears pretty prominent in that latest image.

you are correct, 50 years old, lots of things can happen in those 5 decades.

mikestr

There is no paint upset; it is plastic film, chipped away in places, as you can see. I've scratched away more of it for clarity. It's really stuck on there, too.

mikestr

I see that in the process of scratching away that film I further damaged the sticker. No more. I think we should drop the matter.

dddd

The E and LE that I acquired do have similar steep angles, though the LE is a 60cm and the fancy-lug E is a 56cm size. Both are from around 1974 as I recall.

mikestr

This was my impression. Thanks for confirming.

mikestr

This web page contains some materials I haven't seen elsewhere: https://www.dcisite.be/en/dci-steel-...eugeot-PX-10LE