Me2gingko

First, I want to say thank you for all of the knowledge posted here. I have learned so much in the last few months as I disassembled and cleaned a wonderful 1971 Super Sport. First time doing this type of work. I am also fixing up a 1954 Spitfire that has stolen my heart.

I might be at the newbie phase when I will learn a lesson the hard way! Essentially, have a frame professionally checked before doing anything. But, I was excited about future rides on this Super Sport and plowed forward. During the reassembly phase, I noticed the rear wheel was a struggle to get in & out and discovered the rear stays are out-of-wack. Not too worried because it will be an easy fix. But, I also noticed a curve in the seat tube. I looked online and found the same bend in other vintage Schwinn Super Sport frames for ladies. Most noticeable when fenders are on the bike.

Is this bent or part of the original design? If it is bent, can it be fixed?


Have to love a bike-on-a-table...



Beginning to come together but, is that a curve in the seat tube???



There is definitely a curve!!!



Is this normal?

Thanks you in advance for your expertise and advice.
~Laura

Doug Fattic 

First of all congratulations on getting a very fine vintage bicycle. The Chicago made Super Sports were fillet brazed. That means the tubes were held together with melted brass. The heat from melting the brass and getting the tubes hot enough so the brass will flow around them distorts the seat tube. It will not come apart and it can not be "fixed" and is nothing to worry about. Most people would never notice the curve that was the result of the manufacturing process.

I'll be interested to see how you decide to spread the dropouts apart so the rear wheel can slide into the slots without effort. The goal is to have the dropouts equidistant from the centerline of the frame and the dropout faces parallel to each other. Park among many other tool manufacturers makes tools just for that purpose. Bike stores occasionally have them. Framebuilders like myself always have them.

bikemig 

I love the shot of all the nice clean parts on the kitchen table. That’s classic. That’s a very fine bike to restore.

Me2gingko

Thank you for the reply. I read about the fillet brazed process for this bike, but did not know it could cause a slight curve. I am relieved it is nothing to worry about.

As I mentioned, I am new to fixing up old bikes. I think I will let my LBS realign the rear stays. I have watched videos and know it can be accomplished without too much trouble, but the right tools & expertise makes all the difference. I can let them fine-tune the shifting & brakes at the same time... plus check my newbie work in general!

pastorbobnlnh 

Great project and you did an excellent job. Kool Lemon is always a favorite!

I can't tell if the bend is normal or not. I built the below '69 or '70 Super Sport for my wife well over a decade ago. The bike and frame had been horribly cared for and I ended up using a modern Shimano Nexus 8 speed IGA and dynamo for the wheels, etc. This is the best picture I have for comparison. If I have a chance in the next day or so I'll check the seat tube with a straight edge.

Me2gingko

[QUOTE=pastorbobnlnh;22132227] I ended up using a modern Shimano Nexus 8 speed IGA and dynamo for the wheels, etc.

I have similar plans and probably got them from you in previous posts! I wanted to keep it as original as possible for the first few months to enjoy it as intended, but will slowly make a few upgrades. It is a wonderful bike and I feel lucky to have found one in great shape.

Sluggo

Over in the Frame Builders forum, Andrew R Stewart points out:Here is the thread.

I don't know if that is what is going on here, but it fits Mr. Stewart's description. It does not seem like it would be easy to fix, but also not critical to function or safety, though you might want to use a seat post with a little more setback.

ollo_ollo

Clean parts on a clean cloth in a clean house. Homes are meant to be lived in. When I was younger, the late Mrs. ollo once permitted me to store and re-assemble a small tractor engine in our spare bedroom. It was Winter time and I did not have heat in my garage yet. Don

sd5782 

Don’t be surprised if your rear derailleur doesn’t shift very well. It sounds like you have done your homework and probably know that already. Most have been replaced when someone actually rides these very much. Very nice looking bike, and fine choice, and nice updates.

Me2gingko

Sluggo & Doug Fattic: I suspect it is a combination of both. Initial curve during the making and years of stress on a weak spot. Still not sure if it places the bike into an enjoy-it-as-it-is category, instead of a long-term pet project.

sd5782: It is a fact that the SS’s did not get great components. I have my doubts about the front derailleur as well. Complicating the situation, I had to dismantle it just to get the wire bolt loose! I soaked it in everything possible, but I could not get the thing to sit still while applying pressure on the bolt. Alloy/steel fusion stuff vs 60 year old small female hands. Took it apart to clamp it down, but soon understood why it is best to leave a front derailleur intact. They are a monster to get back together! I hope the tiny springs hold up. These pics should get a few laughs...

This bike has humbled me in many ways…



Had to screw it into a 2 by 4 to gain leverage...



Finally, it came undone... it looks benign, but it was a brute.



Thinking: how does this work again? Had to take more of it apart to get the little adjusting spring back in.



Might be a success, but only time will tell.

sd5782 

Amazing determination. I am humbled. I’ve not had any problems with the operation of those front derailleurs. I would think after your overhaul that it should be good for another 50 years.

qcpmsame 

Very nice build, your organization and attention to detail are really good. I believe Doug and Sluggo gave you good, knowledgable answers to the question about the seat tube curve. I would keep an eye on the welds for the down tubes at the seat tube, for crack formation and propagation. Also, at the seat stays welds attaching to the seat tube. Even paint cracking here will be a give away.

From my experience in fatigue and failure of steel tubing and welds (construction quality engineering inspections) unless you are subjecting the bicycle to some hard riding, and/or heavy loads, it should hold up quite well. These CroMoly Schwinn frames are truly well built and engineered, to the point of overkill and overweight. I'm building up a "kool lemon" Super Sport, 1972 year model now. Its nowhere near the nice condition, patina wise as yours is, but it should provide me a good, reliable around town and campus bike. Just as my '73 Continental did, back in the day, way-way back in the olden days.

The front derailleur, I'd give it a chance, I found an original for my build, getting the correct diameter band is the hard part. I punted on getting the original long cage rear derailleur, they are scarce and pricey. Reading posts from the learned elders here, I found a nice Suntour VSeven, long cage derailleur, on eBay for a decent price. Your cleaning and rebuilding are well executed, Kudos.

Well done so far, please keep us updated as you get things wrapped up, and put some miles on it.

Bill

Doug Fattic 

I have an identical yellow Super Sport (as well as a matching men's) as the OP's. They were donations from a college friend with the understanding that any proceeds from their sale will go towards our charity Ukraine Bicycle Project. We make fillet brazed frames on a college campus outside of Kyiv and then build them into transportation bicycles for pastors in the eastern war zone where only military vehicles as allowed on the roads. The seat tube on the SS I'm responsible for now is also bent just like hers. This characteristic of a tube bending when other tubes are fillet brazed to it is common. You can see this often on the head tubes of fillet brazed tandems. Most people just don't notice.

I've taught framebuilding classes on a regular basis for 45 years. Usually students make lugged frames in class but sometimes they will do a fillet brazed one. Here is a picture of an example a student made so you guys can see what they look like in the raw. This is the top of the seat tube. Of course in this case the fillets have been filed. Some builders like Tom Ritchey or Normal Taylor (the brother that actually fillet brazed Jack Taylor frames that I personally saw make frames when I was apprenticing in England) can flow the brass so it needs little or no after brazing touch up.

Me2gingko

Doug Fattic: that is amazing craftsmanship. The file marks are beautiful as well. I will trust that my SS will be fine for many years. There are no cracks in the paint and it will have a leisurely life going forward. A few water bottles and snacks will be its biggest load... besides me!

Murray Missile 

Nice job! That's too pretty now to ride though.

bikemig 

I just rebuilt a 73 kool lemon sports tourer. Fortunately it had the original parts. Those bikes are overbuilt in good way. Just a really nice riding bike.

Doug Fattic 

Yes my student did a very nice job fillet brazing his frame. I think you'll find your Super Sport with its original components will work just fine for your purposes. It is what I'll call a "go for a walk" model. It is perfect for getting some fresh air or something at the store. For those purposes, the shifting will be fine. Chicago Schwinns were overbuilt so they didn't' have to honor their forever guarantee. That 50 year old steel derailleur can be taken apart and cleaned and be just like new again. Of course a Suntour VGT will shift better/faster but when you aren't riding fast it won't matter. Unless you get hit with a nuclear bomb your frame isn't going to crack or break or somehow fall apart even if you ride as it as hard as humanly possible. The tubing they used was pretty stout and strong and much better than gas pipe tubing used in department store bikes.

My dad paid $96.50 + tax for the Super Sport he got me for Christmas in 1965. That was a shocking amount of money for a bicycle at that time. A few years later it got stolen my last day of college when everyone was leaving campus. A few years ago I wanted to find another one of that vintage so I could compare the ride with modern bikes. I saw a lady riding one on the Apple Cider Century. She had ridden it thousands of miles without any issues. She eventually was willing to sell it to me and I gladly paid her full asking price of either $125 or $150 without haggling since it was worth more than that to me. If it shifted that bad she would have traded it in long before. Pre 1970 10 speeds are much harder to find in the States because that was before the 1971 bike boom when just kids rode bicycles.

If you get more serious about going fast and far you will probably want a completely different bike but your Super Sport will always work great for those around town jaunts. And it looks terrific!

Sluggo

For clarification: are you saying that this curve happens because the tube is heated on one side only?

madpogue 

Even that says maybe. Aren't there remote viewers who see a post-apocalyptic future of giant cockroaches eating Hostess Twinkies and riding '60s and '70s Chicago Schwinns?

Doug Fattic 

Yes, heating on one side curves the tube in that direction. When it is massively heated enough to flow all that brass (it is actually bronze that melts at 1600º) around one side of that seat tube, it will curve a lot in that direction. The cause of the bend on a lady's fillet brazed Schwinn Super Sport seat tube would not come up for discussion on a frame builders forum unless it was a newbie because the cause would be obvious to anyone with brazing experience.

Heat and its resulting distortion is one of the complications of making a frame that is correctly aligned. It isn't easy to do and many vintage steel frames are not properly aligned. When thin wall/heat treated Reynolds 753 tubing came out in the late 70's, they required a test frame to be sent to them before a builder could purchase it for building themselves. They checked it for alignment and cut it apart to check brazing penetration. In talking to the Reynolds representative back then he told me all Americans that had applied up to that point had failed their test. The problem is that heat treated tubing can not be bent (well not much anyway). Old Reynolds 531 was designed so that after brazing, the frame could be bent into alignment.

Me2gingko

Since I am a newbie, I get to clarify even more! After doing a crude string alignment test on this bike, I concluded that the rear stays are a little wacky, should I be aware of anything special when I take it into a bike shop to be realigned? Will a fillet brazed frame react differently to the common ‘cold setting” techniques used on other steel frames?

wonderful feedback from everyone ~ thank you.

dddd

The rear stays should respond to normal bending efforts. The clearance crimps will provide some yielding locations.

Thinking about the bent seat tube, it makes sense that the side of the tube that is the last to cool will shrink more after the brass suddenly cools to a solid state, since it will undergo a greater temperature drop from that point on (the other side of the tube will be at a lower temperature by then, so will not undergo as great of a temperature drop and with less shrinkage on that side of the tube).

Doug Fattic 

As already mentioned, your fillet brazed frame can be realigned by a knowledgeable person without any problems. However not all bike shops have the correct tools to do it properly. At a minimum to work on the rear triangle, they need to have a Park Frame Alignment Gauge as well as dropout alignment cups and in addition a tool to adjust the rear derailleur hanger. It is unlikely they might have an alignment table to adjust the front triangle and a fork fixture to make sure the fork is correctly aligned. It is bicycle frame builders that have those tools

I've attached a picture of one of my tool walls so you can see what those tools look like. Sitting on the very top of the pegboard is the Park frame alignment tool, in the middle (to the left of the wrenches) are the dropout alignment cups and to the right of the hacksaws is the derailleur hanger adjusting tool. If your LBS doesn't have those all 3 of those tools, go somewhere else.

sovende

I’m most impressed with the lack of visible pitting on the chromed components and near pristine condition of the aluminum ones! The paint seems to be without blemish either. Was that bike packed in cosmoline and placed in a time capsule the day after it was purchased? Kudos to Me2gingko for a top notch cleanup . My Dad bought me a “gently used” Schwinn Continental in the mid-60s and it NEVER looked that nice even only being a couple of years old .

anotherbike

Looking closely at the pics of your yellow frame, the braze job at the top tube to seat post doesn't look right to me. It looks a bit chunky or over done.
All of the Chicago Schwinn ladies frames I have here have nearly no visible fillet at that joint, one has a bit on the top and bottom, but its not finished looking.
Including a 1971 Suburban and a 72 Collegiate. Plus I've got a couple ladies Breeze models that are the same way.
I went out back and found a SS ladies frame in the shed, like yours, a 1971, it too has the big chunky fillet around that tube and a slight curve in the seat tube.
The SS frames were supposedly some grade of chromoly so its quite possible that the fillet brazing process did curve the thinner tubing.
Up until I read your post, I don't think I ever paid close enough attention to those bikes. The frame I have here came to me as a bare frame, someone had stripped it to fix a men's model. I robbed it of the rest of its components and put it out back years ago.
After seeing that the frame I have here is curved, I went on a hunt for pics online, and every one I found looks to have that same curve. Including a yellow one currently on eBay now.