I'm thinking of picking up an old Schwinn from E-bay and converting it into a light-weight fixed gear. The main question is, which one? I can't see buying a $$$ Paramount but what else would work?

Nearly any old Schwinn can be converted. It is made easier if the bike in question has long, horizontal dropouts. I'm familiar with many old Schwinn's in addition to the Paramount that would be good candidates and are very well made. Those would include the Superior, Sports Tourer and Super Sport to name a few. They were among the lightest that Schwinn made at the time and the quality of manufacture was very nice.

You can find catalog scans on Tom Finley's site which can be accessed through the Waterford site.

https://waterfordbikes.com/w/culture/schwinn-catalogs/

Also, have you checked out the conversion information in Sheldon Brown's website?

https://www.sheldonbrown.com/fixed-conversion.html

Edit: P.S. Unless you insist on paying more for one, I'd check your local Craigslist for candidates first. I don't think the bay is the best way to go.

I'm not so sure the words Schwinn and lightweight work that well together. There is a world of track bike frames for sale, it takes a while to figure out which way you want to go. Lightest bikes in my garage are aluminum track frames by Cannondale (Capo) and a Cinelli Vigorelli. Leave eBay alone and see if you can find a CL or (better) Facebook marketplace sale.

There are some sellers of SS and Fixed bike in NYC area that have big inventories and good prices. All on FBM. I'll try and load a link in a bit.

No matter which way you go it is fun to own a SS or two

If you want a lightweight Schwinn, just look for one not made in Chicago.

Anything "Made in Japan" from the 70s to early 80s, most of the 80s bikes made in Mississippi are competitively lightweight for the era.

There is one Chicago-made, non Paramount that works well (I built one in '00) and that's a fillet brazed Sports Tourer. Not the easiest thing to find, but they're out there.

I had a ~1980 Japanese built Schwinn that made a super fix gear. I picked the frame up cheap, minus fork, from the local bike shop I'd been in many times after I wrecked my fix gear. (Doored.) The Schwinn had been hit by a car. Rear triangle pushed far to the side. I straightened it and brush painted it black with epoxy, threw the part on from my previous bike and rode it until it was stolen in a college town. Loved the ride. Never noticed the model. Probably a "Sport something". It wasn't high end and feather light but it did (clearly) have butted main tubes and probably not cro-mo stays but better quality hi-ten. Workmanship wasn't spectacular but was very good. Quality dropouts - nice on fix gear though not essential.

I am one who would far rather have horizontal road dropouts than the open-to-the-back track ends. Much easier to deal with when removing the wheel. My fix gears are all road bikes and flats happen out on the on road. Sometimes at night, sometimes in the rain ... For commuters and other fix gears where you are not changing cogs, road dropouts with the locating screws allow you to dial in chain tension. Now, road wheel insertions in non-optimum light conditions can be done fast with correct chain slack and no brains or judgement is required. (If you live car-free and your fix gear is your car - as mine was for decades - those flats and wheel insertions happen when the judgement and brains got left at home.).

My bottom-of-the-line Schwinn Sprint would actually be good for fixed gear. The BB height with 700x32 is a lofty 11 inches or a tad over.

Otto

You make a good point about BB height, something which can really impact whether a particular frame is suitable or not.

Looks like the older ones have that cool s bend in the seatpost - I have been a fan of those since my first fixed gear

This one isn't/wasn't mine. I think the one I had was a size smaller - same model and color though... it must have been 2005 or 2006 since I bought my second fixed gear, a Pista Concept used in 2007. I saw it hanging in the store, complete bike, tig welds and crazy seat bend. With the silver grey color it looked so industrial and wild to me. I'd never rode any kind of fixed or track bike but something about it whispered "ride me". $700 later and it was mine!

Very nice. Mine happens to be from the later 80s era which is a lugged frame made in Taiwan and simple straight tubes, no S curve. I checked and unloaded BB height is 11 3/8” so loaded I would expect the average height to be about 11 1/8” which is pretty comfy.

Otto

Any old road bike with horizontal dropouts will work for fixed.