Hi all,

I am searching for a seatpost that can get the saddle to move further back on my pug if anyone has any suggestions or links . Doing it because I would like to mount a brooks B17 saddle which is known for its short rail lenght and also because I have a much better feeling of power on the pedals when I am back about an inch which the current saddle wont give and forces me to sit uncomfotably far back on .The current saddle has only one position on the rails for clamping and no scope for adjusting fore aft. The current seatpost has the old style clamp and not the micro adjust one . I will also be trying other saddles to see if I can manage to make the bike fit but I would rather a seatpost thats further back than a saddle pushed back to its extremes on the rail with all my weight on the unsupported end .

I am aware that this could be difficult to do due to the awkward french seatpost diameter . I have measured the seatpost diameter and it comes out as somewhere between 24 and 25 Mil maybe even a hair breath more than 25 mil , hard to measure by eyeballing with a ruler . I will try and get my lbs to do a more accurate measurement with calipers .

I am wondering if it would be ok to sand down a larger seatpost if needs be or would this be suicide ?The best I have come up with so far is this velo orange grand cru , expensive and too wide a diameter and a shame to sand down such a nice part but its an unfortunate possible plan A. Here is the link so you can see what I am after .

VO Grand Cru Seatpost, Long Setback

I can understand arguments about getting a bike that fits but this pug was given as a gift and if I could just tweak it to be a bit more comfortable it would be a bike for life .

You need a better measurement of the seatpost diameter, which your LBS can do. After that, it should be easy to get a seatpost of the required diameter. Your LBS can order one, which is the route I think you should take, because if the new post doesn't fit, they will take care of getting the correct part or honing the frame. If it is an unusual diameter, like 25.0 mm, or an unusual seatpost type, like a quill seatpost, then it will take a little more looking. But generally it isn't especially hard to get a seatpost for a Peugeot.

However, if you really need a full inch of additional setback, beyond what you already have, that may limit the selection of seatpost quite a bit. You may want to instead, or also, use a different saddle with longer rails. Don't worry about having the saddle all the way back on the rails.

Yes, you can sand down a seatpost, but only a little. Like 0.3 mm or something similar. Going from 27.2 mm to 25.4 mm would be too much sanding to be practical, and maybe more than would be safe.

What model Peugeot? Picture?

I have the solution for you. I just removed this set back adapter from a seat post. It will fit a single bolt clamp style post. See the pictures. This is the first one of these I have ever seen. Third picture shows the same post with the adapter removed.

Another possibility is to get a selle anatomica nsx saddle. They're fine saddles and have a long rail. I used one on a recent build precisely for that reason. I think you can still get one for sale at $99. I recommend it both as a saddle and as a solution to the problem you are having.

Also if the bike is too small, you may need a bit longer stem as well.

Here are a few pictures , there is no more that the saddle can be moved back . Model is a Talisman ph8 late 70s . May not be familiar to some from North America as I am posting from Ireland .

While searching for a set back adapter I came across the Brompton seat pin ,looks ugly but it might just do it and save me searching for a rare seatpost size , any one have experience with them?

Laid back 1" BMX post.

25.4mm

Redline Chromoly BMX Bike Seat Post Laid Back 16" x 25 4mm 1" New Lay Back | eBay

Ok, it does not look like this was one of Peug's top models of the day, though as ever, they were known for giving you a fine ride for not much money.

To get more saddle setback, I think you have all the info you can get - more setback with a seatpost that can offer it, or more setback with a saddle that has long rails. Long rails means to me, you need a Specialized saddle such as an Alias, or a Selle Anatomical saddle.

Your existing seatpost/clamp has a setback of about 15 mm roughly. Similar setups I've measured fall in this ballpark. Deep-setback posts like the one Wk101 showed you could reach back another 15 mm again roughly. When I have the kind of problem you are talking about, that is enough to help me.

Can you measure your seat tube angle? A different frame with a more laid-back (72 degree versus 74 degree, for example) could get you more than another centimeter of setback.

Is this a bike you love? Is spending a couple hundred dollars to get the seat completely right worth it to you? If yes, consider having a custom post made. Then you can specify any setback you like. I had two customs made with conventional straight seattubes, but set up very steep so I could get the rear wheel forward so I wouldn't spin the tire climbing out of the saddle with my weight far forward. But this meant either the seatclamp right at the forward turn of the seat rail, a great way to break expensive ti rails or the seat to far forward. So I had 160 mm setback posts made. My clamps are near perfectly centered on the rails and I have a lifetime's worth of adjustment.

TiCycles did my posts. They machine the seatpost clamp from bar stock so any distance and post diameter is possible (as long as they can get the appropriate tubing; I am sure they can machine some down in a pinch). Mine are 160 mm setback. The clamp parts are the excellent Thompson clamp top and bolts. The posts are a joy to set up and adjust.

Ben

Hi wrk101 ,

Any idea where I would find one of those ?

.
...look on Amazon. Get someone to measure it and get the correct size (which might be marked on tour old post.)

https://www.amazon.com/FSA-SL-280-sea...tback+seatpost

Robot Check

Alternative: Consider just adjusting your riding style to one more over the seat tube, spinning your pedals at a faster cadence, and just get a longer stem.

It's the 24mm that's hard to find.
I went with this one.



Alu Patent Sattelstütze 24 mm Durchmesser Diamant DDR Mifa 350 mm Länge | eBay

Jambon, I think your fork is bent.
Yes, I know I'm a buzzkill...

The Peugeot models prior to 1979 that used the 23.8 or 24.0mm seatposts had relaxed seat tube angle to begin with, and with a steeper headtube angle.

1979 and later models that still used the skinny seatpost had a much steeper seat tube angle and with a relaxed headtube angle. These were the 103 tubing frames with properly brazed-on cable stops (instead of the prior spot-welded sheet-metal stops).

I wouldn't recommend a heavily-offset saddle arrangement for any but the lighter riders and for gentler use on decent roads.
Such setback can cause enough stress to fracture a bolt, crack a seatpost casting or bend seatpost tubing.

It sounds like someone is perhaps trying to make a cruiser out of a road bike, at least it seems like that's what they will likely end up with.
A post-1978 model might actually handle ok with such a setup, but a particularly sturdy post is recommended.
A pre-1978 model should handle well with a longer stem as a way toward an expanded cockpit, and I have done this with good results.

Yes .. a Brompton SAP takes a straight post and adds a horizontal tube on top so set back is an adjustnent, depending on your saddle clip location ...

Buying a 25.0 or 1" seat post and reaming out the Post ID to suit ** will make life easier

your seat post size is small because the tube wall is Thick and Metric ... 28.0mm rather than everyone but France * 28.6 OD. 1.125"
*they have since fallen back into the world standard.

** I Used the LBS's Adjustable reamer.. less cutting as I had A higher end frame Thinner tube wall so 27.0 to 27.2 was all I had to remove [0.1mm]

Not sure of the available diameters but consider the vintage SR MTE 100 offset seatpost.

There's lots of meat in them, so one could also machine turn them to fit the seat tube.

Interesting , do you think that from looking at the pic I posted of it sitting outside against a tree ? The guy uncle who gave it to me said it took a hit from a car in the front / fork . But the wheel sits perfectly into the front dropouts and is aligned with the rest of the frame so I have thought nothing of it .

Nice I think this looks like probably the best option

Thanks Ill keep this info in mind . I am wary of having too much pressure on a seatpost extension and I am a heavy guy . As far as tweaking the bike to be more like a cruiser , I am just trying to get the fore aft correct , as it is I have to sit with my butt hanging off the edge a bit for a powerful pedaling feeling .