June 17, 2025

Restoring my Peugeot PX-10 - Tires

I am going with 700C wheels, so 700C tires. Probably 700C-25. You can get really skinny -23 tires, but I am no racer. And there are wider tires too (-28, -32, -35, -38 and wider).

I suspect that really wide tires are going to require a suitable rim, and the really wide ones will have trouble getting mounted and slipping past the brakes. The general rule is that unless you have disk brakes, you are limited to -28 for this reason.

Some frames will limit tire size. The tightest spot is usually between the chain stays near the bottom bracket. As far as rims, if the inner rim dimension is 23 you can put any tire on, but if it is the narrower 20 you have to check specific tires. Tire manufacturers will tell you what rim width their tires fit on.

People recommend -35 and -38 tires for commuting these days, but others say that this is all the current fad. People commuted for years on -23 and -25 tires.

My rims measure 20mm on the outside, so they may well be 17mm inside.
The narrow place on the Peugeot is about 35mm.

I will go with presta valves, like always. My pumps are all set up for presta. You can watch this video and learn about other options and why presta is the worst.

Bulletproof tires

I have always leaned towards heavier puncture resistant tires like the Continental Gatorskin. If you don't mind extra weight and value durability above all else, this is the way to go. The latest thing of this sort from Continental is called the "Hardshell". I hear the Specialized Armadillo addresses the same concept and is well regarded. I have never been disappointed by Continental and remember some misery long ago with Specialized, so I tend to avoid them now.

Wired versus folding tires

This is all about the bead. Boiled down, folding tires are lighter and more expensive. You will find that premium tires are only available as folding tires, quite to my surprise. Some people wonder why wire bead tires are even made these days. Once mounted, a steel bead offers no advantage. Folding tires offer easier flat repair when you can get to the problem without removing the entire tire. Easy of mounting is variable and may depend more on the rim than the tire.

So folding tires are the new normal.

Some candidates

I am no longer a commuter, but am now a pleasure biker. This means I may be able to ride on some lighter and more performant tires without undue suffering. I'll also note that all of these "premium" tires are only available with folding beads (see the above). I used to think wire bead tires were stronger and better, but I was wrong. Don't hesistate, like I used to, over folding tires. The Continental GP5000 gets outstanding reviews. I see various letters (TR, AS, ...) and who knows what they mean. I am told that many tires these days fit very tight and are a bear to get on -- all because many people want to run them tubeless. The Pirelli advertise themselves as "tubeless ready", which is another topic entirely.

You can get more details (and maybe better prices) at places that specialize in bicycles.

Performance has free shipping over $99. Their price on the GP5000 S TR is $96 though. Compare to $74 at Amazon (and with 2 week shipping from Japan!)

Pirelli Cinturato Velo

I found the Pirelli Cinturato Velo in 700x26c on Amazon for $47 each and bought a pair. Some reviews say they beat the Gator Hardshell for puncture resistance. The diagram on the box shows that they are intended for "endurance", but the are possible for use as a "performance" tire.

Continental GP 5000 S TR

I can buy two of these on Amazon for $85 apiece. The bike shop sells them for $92 or $95. What about the "S TR" business. Apparently "S" is for standard, as compared to "AS" for "all season". If I expected to be riding on mud and snow the AS might make sense. The "TR" stands for "tubeless ready". So we have cracked the code! There is also a "TT TR" which sacrifices puncture resistance for speed, it is thinner and lighter.

I want the S TR.-- and I found them 700C-25 for $75 each on Amazon.

Rim compatibility

My Continental GP 5000 S TR tires arrived. All folded up (certainly more civilized for shipping). The box calls the size 25-622 (700x25C). The size with 622 alarmed me briefly, but this is actual dimensions, whereas 700C is sort of a nominal convention in the industry.

The Continental comes with an instruction sheet in 14 languages. It has a section on tire/rim compatibility. 

Well base rims -- 16 or 18mm
Hooked bead rims -- 13, 17, or 17mm
It is unclear what a "well base rim" is, but my guess is that it is a rim intended for tubeless application and is not what I have. My rims definitely have a hook and I measure the width inside at 14mm (with calipers on the hooks).

The Pirelli tires are 26-622 (700x26C). They have a diagram showing the 26mm tire being mounted on a 15mm rim. They have a pressure chart showing the 26C tire used with a tube, and a 135-163 pound rider using 90 psi. So 90 psi for me. Tubeless pressure would be lower.

Have any comments? Questions? Drop me a line!

Tom's bike pages / tom@mmto.org