That looks just about the same as the gravel bikes I made in the 60s and 70s. Schwinn bikes like this were pretty easy to find at thrift stores and many had the 26 x 1 3/8 tires (I think they were called S-6). I didn't know back then that Schwinn had a different size tire until I tried to fit a tire and no one had them where I lived so I put on other wheels from other thrift store bikes. Back then there were a lot of old cheap 10 speeds with 26 x 1 3/8 wheels. My first Schwinn was probably a Collegiate or similar bike as it had the narrow 26 inch tires and drop bars and was sprayed black, over everything. I probably paid $4 for it. Most often I just made a poor mans single speed by eliminating the rear derailleur. I also had some with gears and some with a coaster brake and flat bars. I always had two and sometimes three of these bikes as loaners so that my friends could trail ride with me. I used to throw them in my boat when a bunch of us went camping and we would gravel ride when we weren't fishing. That blue Schwinn is already a gravel bike. It's got drop bars, easy to reach shifter, big rear cog and brake levers on the flat part of the bars. I would just put on a smaller front sprocket. It's almost a perfect gravel bike as it is. 26 x 1 3/8 wheels, the size from old English bicycles, would fit on there and you could get tires cheaper and easier. In the 1980s Columbia made an inexpensive heavy 10 speed with this sized wheel. Take it from one who has ridden this type of set up for years, it's a lot of fun. For what you describe as your rides it should be perfect. If you ever decide to ride 10 or 15 miles of gravel, well this bike would be just great for that distance.
Here is an old 10 speed with 26 inch cruiser wheels that I used for winter and gravel about 4 years ago. It was a loaner for people who came to visit us and wanted to ride. All we have is gravel. It's now long gone to the scrap drive.
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Here is one of my original 70s gravel bikes but the only thing the same now is the frame and fork. I rebuilt it last year for the unofficial March build off. It's not the same now as this picture is about 5 years old. It now has upright bars, like it did in the 70s. I rebuilt if for the Unofficial March Build off so it is very similar to the way my gravel bikes were in the 60 and 70s. I used the frame and made it like I used to ride them for nostalgia and to have one for my collection. It's like Lincoln's hammer, everything has been replaced so much that almost nothing is the same as it was.
A few years ago:
View attachment 113522Now with a Sachs coaster brake and steel 26 x 1 3/8 rims. A long time ago I rode a similar bike 20 mies of single track on a horse trail. Couldn't do that now with this bike. One of my buddies from the fishing days still rides with me and we are in our. 70s. He called these bikes "medicine bikes". He said "you remember when we were mountain biking before there were mountain bikes"? We rode hiking trails, two track and gravel. Our rides were nothing like real mountain biking.
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