June 18, 2025

Restoring my Peugeot PX-10 - Seat and seatpost

As for the seat, it will be hard to get me to try something other than my Brooks B-17, but we shall see.

Seatpost

I grabbed my metric calipers and measured the ancient seatpost from my Peugeot PX-10. I see 26.5mm. I measure the post on my hardtail MTB and get 27.2 (which is a common standard these days). The post on my Surly Ice Cream truck is bigger yet, and the post on the Trek I have been stealing parts from looks like 27.2

I have run into this before. There is for all practical purposes no standard seatpost diameter, which is both surprising and unfortunate. Pehaps even stupid.

Looking at the huge tables in the following, I see both 26.4 and 26.6 documented for the PX-10. Even 26.2 for a 1984 vintage PX-10.

The next Amazon seller offers their post from 25.4 to 31.6 -- The second listing has a diversity of sizes from 25.0 to 31.8 at every 0.2 mm step. They are cheap -- $25.

Brooks B-17 vs C-17

I own two B-17 brown leather saddles and swear by them. I recently discovered that they have an alternative model (launched in 2013) Called the "Cambium" or C-17. It has no break-in and uses rubber and cotton rather than leather. No maintenance either.

The standard B-17 sells for $126. The special edition with copper rivets is $196. The C-17 sells for $93 and there are also special editions (like a "recycled nylon" for $170). Note that the C-17S is "short" and intended for women.

One person comparing the two says, "Once adjusted and broken in, the B17 saddle provided comfort I have never before experienced on a bicycle."

One thing people say is that leather is more "slick" and this is good as you can slide around on it as needed. The C-17 is vegan (no leather), which will appeal to some. The general consensus seems to be that a broken in B-17 beats the C-17, and the maintenance is entirely minimal.

Have any comments? Questions? Drop me a line!

Tom's bike pages / tom@mmto.org