I have a 70's Bridgestone I just converted to a single speed. (Many thanks to the help I found on here!) I have the original quill seat post, but it's super heavy. I've since discovered that quill seat posts are very rare. I talked to a machine shop who can make these. Is there enough demand for these to pursue this? I could do different diameters and lengths.

I'm not entirely sure I know what a quill seat post is.

I need one for a aluminum Schwinn.

Seat post for collar-less frames. It expands inside the tube like some handlebar stems.

I need one for my 1907 diamond frame

All of the late eighties/early nineties Schwinn "Aluminum" bikes used the 27.2 SunTour "Expander" quill seatpost, and they are very rare. I'd have to guess there's a market.

Any reason that Bridgestone needs a quil post? It appears that there are clamp ears on the seat lug to use a standard seatpost.

And it looks llike you seatpost is backwards. Unless that's the only way the clamp angle can work.

That's a steel seatpost without a built-in clamp - identical side to side as it is back to front. The clamp is a seperate piece, though it is generally installed facing rearwards.

-Kurt

Demand, yes. Enough to make it worthwhile to fabricate them? Doubtful.

That's part of what threw me off. I had a Bridgestone pass through my hands a couple of summers ago that had such a seat post. On the one I had it looked just like a standard Steel Seatpost with no built-on clamp and there was a nut at the top of the post to tighten the expander.

The bike in the OP appears to have seat clamp ears.

Ha! Yes. backwards. I did a dry fit and threw everything together to take a pic. Everything is loose. I realized my mistake after I clamped the clamp to the saddle.

It's not a seat clamp. It's just a hole/tube where a rear rack attached to previously.

A HA!
clever.

As someone pointed out on another thread a year or so ago, it shouldn't be hard to make your own. Take a steel seatpost and a sacrificial stem with a long neck. Use the expander bolt and expander from the stem. Cut the bottom of the seatpost to accommodate the expander. Use a washer at the top of the seatpost. Voila!

Do you know of any stems that use 27.2 expanders or wedges as that is what you would need for an Aluminum Schwinn. My 564 has the original post but I would love to get it up just a bit more and that would require a longer seat post.. Roger

I've made one myself, but only because I had a quill gaspipe post already.
Since I already had the bottom wedge nut and the uber-long bolt, I only had to drill down through the seat clamp assembly.
It took 3 drill bit and a trip to my neighbor's drill press, but it worked fine.

By the way, they look great on those Schwinns. Clean, clean.
I've often wondered if they could be made for the Cannondales, too.

I don't think they came with a rack, but they did come with centerpull brakes that required a place to bolt on a hanger.

I solved the problem by modifying a cheap Laprade post. Drill and countersink for the very long bolt and cut the bottom of the post off at an angle. Either use the original steel wedge or fashion one from the cut off piece of post

Nice work! Wow.

The expander for a stem would not work. The diameter is much too small.

Those Bridgestones were rebranded as Canadian Supercycles in the 70's too. Look closely and you can see the raised, fake filed lugs on the surface of the plain lugs. Faux lugs give extra weight and stability!

Gotcha. But using the wedge you cut off the seatpost is brilliant.

i love the finishing work on that seat post, grand bois.

i can see this as a good way to fool the above-average bicycle thief. "where's the seatpost bolt? i need this expensive looking seat!" all one would have to do after setting the post correctly is super-glue a ball bearing into the bolt head that holds the saddle on, and you'd never have to worry again.

of course, now that i've said it some enterprising individual is either going to start marketing this as a city bike security device, or bike thieves are going to start carrying acetone. darn.

If you can produce them affordably, I think the market may be there.

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