The VARSITY's rear derailleur won't work on the '73 SUPER SPORT. (the SUPER SPORT has 14-32 freewheel, the VARSITY has 14-28).
Nothing is different as far as the Ashtabula 1 piece crank and the 52/39 steel chainrings.
( I don't know why you are concerned because it appears that the '73 SUPER SPORT's crank and chainrings WILL CLEAN UP like new, as there appears to be no chrome loss or pitting...........................mesh copper pot scrubber thingy and Comet cleanser(powder)........dump an ant hill type pile of Comet on to a throwaway paper plate or on to a used tv dinner/microwavable instant tv dinner plastic tray...............Wet the ant hill mound of Comet only slightly to make it "wet enough" to be sort of like a paste......Use the copper pot scrubber.......dip or dunk it into the moistened COMET cleanser...........scrub the chrome crank arms and chain rings until it appears like it did in 1973.
The VARSITY rear derailleur, a Huret Allvit, is a POS compared to anything Shimano or Sun Tour. DON'T USE THE HURET ALLVIT, though it is among the best functional of the European rear derailleurs, it is light-years behind Sun Tour and Shimano. The shimano built GT-100 that came on the 1970 Suburban 5 speed and on the 1970 Collegiate 5 speed is five times better than any Allvit, though the GT-100 might be the heaviest rear derailleur ever built during the bike boom era. The GT-100 was seen from 1970 until about Feb 1974 at the latest.......................THE GT-100 was INSTALLED ON SOME VARSITYS WHEN THE CHICAGO FACTORY PRODUCTION LINE WAS OUT OF ALLVITS.........Count Yourself LUCKY if you've got a VARSITY with the GT-100 rather than the Allvit. They are that much better than the Allvit. (There is a MARCH 1970 BICYCLING Magazine article on why the magazine's technical staff had determined that the new GT-100 is the most durable rear derailleur they had ever tested up to that point in time)
..................The Allvit wasn't too bad. IT WON'T WORK BEYOND 28 first gear Cog, but for a European rear derailleur it does 14-28 more than okay, just not as nicely as the Japanese units do and not quite as dependable and durable as the Japanese units are.
.......................SCHWINN had SHIMANO's new 32 first gear cog FREEWHEEL ( model J) developed in the late sixties for the 1970 COLLEGIATE 5 speed and New For 1970 SUBURBAN 5 SPEED model. Schwinn engineers requested that SHIMANO build for Schwinn a Lark like rear derailleur that had a Schwinn engineering specified bash guard and unique locations for the high and low limit adjusters, and a unique cable saver which in itself was very simple but brilliant. The GT-100 is kinda funky looking as it is 100% Shimano but it looks like it is a Lark, that on its exterior looks a little like an Allvit.......Schwinn wanted it done that way in the late sixties for 1970 model COLLEGIATE & 5 speed SUBURBAN. THE REASON THAT THIS NEW REAR DERAILLEUR WAS Essential IS BECAUSE NO EXISTING European Rear Derailleur Was Capable of Reliably shifting anything beyond a 28 cog at that point in time. THE JAPANESE developed rear derailleurs that COULD SHIFT 32 and of course the JAPANESE developed the freewheels with the big 32 cog and then 34 cog freewheels. The Europeans could not, at that point in time(1969-1970).
..................The GT-120 replaced the GT-100 on 1974 model COLLEGIATES and SUBURBAN 5 speeds and the GT-120 has limit screws in typical Shimano location as it is essentially a Lark/Skylark with neat chromed bashguard embossed with GT-120 and cable saver function.
The disraelli gears website is WRONG on both the GT-100 and the GT-120, as disraelli gears WRONGLY states that the GT-100 and GT-120 are 28 Maximum Cog, WHEN IN FACT BOTH THE GT-100 and the GT-120 are original equipment for 32 Cog.......and they easily and flawlessly shift the 32 Cog as the 1970 onward Collegiate and 5 speed SUBURBAN did have 14-32 (model J ) freewheels. (the GT-100 was original equipment on 1970 -1973 Suburban 5 speed/Collegiate 5 speed models, the GT-120 was original equipment on 1974-1977 Suburban 5 speed/Collegiate 5 speed models before FFS )
My advice would be IF BOTH BICYCLES are the size that you can ride comfortably....(BOTH look to be 24 INCH FRAME SIZE).......you should build them both as riders. THE SUPER SPORT has different geometry than the VARSITY does. The angles are less slack on the SS. The ride is more predictable and stable on the VARSITY as it would be the easier of the two bikes to ride with no hands as we were known to do in 1972 when we were all young, dumber, and perhaps stupid, when a trip to the E.R. probably only cost about what three 8 track tapes cost at retail in '72. The Super Sport is a slightly bit more responsive to the rider's steering movements.....quicker to happen....more nimble and manueverable.......perhaps easier for an idiot to carelessly crash........
Build both of them........ Keep the 1 piece crank on both.....................The WEIGHT won't hurt you......you're not gonna be setting any speed records anyway, even if you were to lighten them as much as humanly possible. For the VARSITY.......find the model J (14-32) freewheel from the Suburban 5 speed/Collegiate, so that you have better useable gear range that will let you handle HILLS better (****this will also give you the EXACT same gearing as the SUPER SPORT***)
The SUPER SPORT has original equipment aluminum wheels, where the Varsity has steel wheels.
Hey you know that the CONTINENTAL & the SUBURBANS have the tubular front fork........the VARSITY has the Ashtabula forged blade fork.
Continental has CENTERPULL Weinmanns while the SUBURBAN has the exact same L.S. 2.4 Weinmann SIDEPULLS that the VARSITY has.
The 1970's era CONTINENTAL has the (S) stamped alloy stem and aluminum drop bars.
******the SIDEPULLS are more than Okay on the Varsity with its original steel wheels IF YOU INSTALL KoolStop brake pads AND YOU DON'T RIDE DOWNHILL
IN THE RAIN!
....................suggested: INSTALL SUNTOUR rear derailleur (or Shimano) on both the SUPER SPORT and on the VARSITY also...... NO Allvit, NO CAMPY, No European rear derailleurs period.........JAPANESE EXCELLENCE ALL THE WAY IN THE REAR DERAILLEUR DEPARTMENT!!
........................suggested: for the VARSITY......remove the drop bars and obtain/buy USED SCHWINN 7881 handlebars and Weinmann tourist brake levers.
The 7881 handlebars were in use for about a decade or so from beginning in 1967 model year until around 1977.
7881-67 indicates 1967, 7881-75 indicates 1975, 7881-71 indicates 1971, you get the picture as the two numbers after 7881 hyphen indicate year....THERE ARE NO DIFFERENCES, THE CHROME IS NOT BETTER OR WORSE IN ANY YEAR, The Year just tells you when it was made......THESE HANDLEBARS WERE ORIGINAL EQUIPMENT ON MANY DIFFERENT SCHWINN MODELS, the BREEZE, the Collegiate, the Suburban, to just name a few of them....
.................The Weinmann tourist brake levers from about 1964-1980 ARE ALL THE SAME TOO......red dot knife edge, red dot ball point, gold dot, WHO CARES AS THEY ARE ALL FUNCTIONALLY EXACTLY THE SAME with (22.2mm) clamp for 7/8" outer diam(22.2mm) handlebar dimension. The Dia-Compe tourist levers of that era are virtuallly the same essentially clones. Cannot be any easier as the old Weinmann tourist levers are well built, lightweight, install with a flathead screwdriver, look great, and durable and function flawlessly and they don't look like dog doo as some of the old tourist levers that came on old Raleighs or Peugeots did.
.............suggested: BELL PITCREW 600 cable set (approx $10 to $13 depending on retailer/website/Amazon) and you'll need a $16 no-name, red handle Brake Cable Cutter(bikesmiths sells it, as do some other Ebay vendors) as this no name cable cutter is a clone of the PARK TOOL & PEDRO's versions at a fraction of the cost.
I have done cable replacements on more than 35 bicycles in the past three years with this exact no-name $16 Brake cable Cutter and it has functioned perfectly thus far.
Will it last as long a the PARK TOOL version, probably not, but are you gonna need to do a hundred bicycles or more?.......if not, it won't matter, the PARK TOOL won't do it any better for at least the first 39 bicycles or more.
.............The BELL PITCREW 600 cable set INCLUDES THE aluminmum ferrules that attach to the WEINMANN tourist levers (where the cable exits the Weinmann-DiaCompe tourist lever) The ferrules look and fit perfectly. No need to worry about if you are missing them, or if they are beat up, or whatever because these ferrules are included in the BELL PITCREW 600 cable set.
suggested: If the SUPER SPORT's KOOL LEMON ("yellow") paint isn't missing paint in too many locations, clean up what you have, INSTALL reproduction decals and away you go with a super nice SUPER SPORT.........................no joke, the Schwinn chrome on crank and front chainrings will clean up like new in most cases where there is only minor rust corrosion. If the paint is really bad (it doesn't look that way) but if it is, you can always repaint it yourself or have it powder coated. RUSTOLEUM has a couple of yellows that are very close.....one in the oil based--paint can variety.......one in the spray can variety......and yet another in the safety marking--industrial yellow marking YELLOW color used for marking lines etc for OSHA and safety compliance(avail in both spray and gallon/qt sizes) See HOME DEPOT.
I got a perfect touch up on a 1972 Kool Lemon Collegiate by bringing the bicycle to the paint isle at Home Depot in Jan 2017. I asked at customer service desk if I could bring the bike inside the store to try to eyeball match color with existing off the shelf paint offerings.....they said sure.......... Nothing brings a smile to overworked, poorly paid, hard working Home Depot employees than an ancient Schwinn in the store in January when the weather is cold and dreary outside. No less than three Home Depot employees assisted in test spraying and blotting can paint on to a scrape piece of pipe and a piece of metal..........they all rode it inside the store too....the mgr did it too, said it was a needed morale boost....it was a weekday, early afternoon, on a bitterly cold day in mid January when business was slow.
Now the 1972 Collegiate had spent its life in the 100F sunshine in the Deep South USA, so the existing Kool Lemon had exhibited significant sun fading compared to some known Kool Lemon bicycles that had been stored away from direct sunlight for most of its years.
Do Not Go with any Huret Allvit rear derailleur (or anything European) no matter if it it is a later Allvit or a special Allvit version with greater capability!!! Go SUNTOUR or Shimano!!!
My 1971 SUPER SPORT has 32---26---21---17---14 at the rear (stock original equipment from SCHWINN)
the VARSITY-CONTINENTAL-10speedSUBURBANmodel---and the1964 thru 1969 Collegiate has 28---24---20---16---14 at the rear
the 1970 - 1976 Suburban five speed and the 1970 -1977 COLLEGIATE (before FFS came in late seventies) has 32---26---21---17---14
(****AS YOU SEE, LOOK AT THE Seventies era SUBURBAN 5 speed and the 1970 and later COLLEGIATE to Give your VARSITY or Continental the SAME GEARING AS THE SCHWINN SUPER SPORT HAS*****) ditto for the 10 speed Suburban as it has the same exact 14-28 gearing as the Varsity-Continental.
The TWIN STIK (s)(s) and (S)(S) Schwinn stem shifters are great! Yeah, they are heavy, but if you were born in the 40's or 50's, you recall "HEAVY" was a cool expression from about 1968 through 1972, as were the expressions: "OUTTA SIGHT" and "FAR OUT".
You will NOTICE that the (s)(s) on your 1973 SUPER SPORT has a funky looking ess that is a smaller funkier looking "ess" , and the 1974 and later SCHWINNS including your late seventies VARSITY have a TWIN STIK (S)(S) where the ess is looks cleaner and larger.
The LATER (1974 onward) (S)(S) style is said to be more efficient as it said to pull more cable but both work flawlessly.
You'd have to find the detailed analysis and explanation from Schwinn expert of experts, METACORTEX, on the subject of the differing TWIN STIK generations.
Like the classic old ISLEY BROTHERS hit from '69......."ITS YOUR THING, DO WHATCHA WANNA DO..."
The VARSITY will make a UPRIGHT TOURIST BIKE if you upgrade the freewheel from the existing Varsity 14-28 to the 14-32 from Suburban 5 sp / '70 onward Collegiate.
You already can probably salvage that UPRIGHT TOURIST seat that is currently on your Super Sport for use on the VARSITY.
The 1 piece Crank is a engineering marvel of simplicity and durability. DO NOT FORGET THAT THE ORIGINAL SCHWINN #64 caged bearings in the 1 piece crank are superior in quality to replacement new aftermkt #64, assuming that the #64 original SCHWINN caged bearings are in excellent shape.
Don't worry though because the available aftermarket #64 caged bearings are very good, but nobody ever made bicycle bearings to the quality of those sixties and seventies era SCHWINN bearings as the ball bearing steel quality and material was way better than any bicycle ever needed.
Clean the old ones by soaking them in FORMULA 87 in a cut in half 12oz (355ml) COKE can. Formula 87 is what was recently at $5 per gallon, and powers your lawnmower, your SUV, your pickuptruck and your car......also known as 87 octane, REGULAR, ..........
Use a 7 inch piece of coathanger bent like a J to fish the #64 caged bearings from the soak in the cut in half Coke can.......DO THIS OUTSIDE, AWAY FROM SPARKS, FLAMES, PETS, CHILDREN, BUILDINGS.... you only need a few ounces of formula 87......just enough to drown the bearings to clean them.
I recommend that you use GREEN GREASE (brand name, located out of Texas), its a waterproof synthetic automobile-marine grease that is available at all major auto parts stores, it comes in a 14 ounce plastic canister for a grease gun..........you can simply open one end of the 14 oz plastic canister and spoon out the globs that you would need, when you need to.......... rubber bands around a piece of Reynolds Wrap aluminum foil will adequately cap the container for future use. Cost of the 14oz canister is approximately $11. You will not find a better grease for 1 piece cranks than GREEN GREASE, at any price.
Yeah, any military spec automotive grease from 1942 would do the job adequately, assuming that grease is fresh and clean, but you will not have the waterproof synthetic property of modern GREEN grease. As you know, the 1 piece crank is susceptible to potentially getting water in there in more extreme / wet conditions. Still, it would not matter if you regularly remove clean and regrease with whatever 1942 era grease, thus keeping it always clean and freshly greased. Grease is extremely inexpensive. Get the good stuff. No need to overpay for Phil Wood or Ron Wood as that certainly is not any better than GREEN Grease when it is for a 1 piece crank application. All other Synthetic Waterproof Automotive/Marine bearing greases are equally as good for use in a 1 piece crank application.
Have fun with your SCHWINNS.
They ride better than most who have never considered them, would expect them to.
There is no law that says you cannot own and ride multiple bicycles.
There is probably a place for at least one old Chicago SCHWINN in everyone's collection.
Stay Thin, Ride A Schwinn, their extra weight will give ya a better workout!