swampyankee2

In the time I've perused the ads looking for a nice vintage 10 speed, I've been attracted to the old Schwinns and in my research found that the Super Sport has that filleted frame look of the classic Schwinns but lighter than the flash-welded ones. About the only thing I hesitate about is the forged crankset. But I just read an old thread that mentioned an adapter kit that will convert the old forged cranksets to cotterless. Unfortunately, the company they referenced selling them is the now-defunct Harris Cycles.

Is there anyone else offering this conversion kit?

BFisher

Here's one.
Truvativ Adapter

bikemig 

Alternatively, get a Superior or a Sports Tourer as they came with a conventional BB.

This is a good discussion of the fillet brazed Schwinns:

https://www.sheldonbrown.com/schwinn-braze.html

pastorbobnlnh 

"Sporty" no longer resides in NH and is currently enjoying the sunny south in its 51st year. The modification of a Super Sport or finding the Sports Tourer or a late '70s Superior, is very satisfying.

I do have a green Sports Tourer still in NH which needs a new home.

swampyankee2 in what part of New England do you reside?

sd5782 

I found a crank arm adapter that uses the Ashtabula crank and any 110 rings. The setup is one pound heavier than the 3 piece crank but is easier to service and probably more durable. I posted here on it. They may still be available on the web.

dedhed

https://porkchopbmx.com/bmx-bicycle-...-crank-chrome/

nlerner

I've used that Truvativ adapter on a Super Sport. One note is that you'll also need to use a cartridge BB rather than a cup-and-cone model.

RustyJames 

I did this exact thing on my SS and it worked well.

**Note - you will need to do some grinding inside the BB shell to make the Truvativ adaptor fit properly.

swampyankee2

Its about my only hangup about those classic Scwinns. That clunky, heavy steel crankset. The adapter sounds like a great solution.

RustyJames 

I’m sure you could find a decent crankset from a forum member, if you don’t have one already, and the conversion+BB will cost less than $40.

Jeff Wills

Or, if you have a lathe and/or a friend with machining skills, you can modify the adaptor like I did on my three-speed Super Sport:

Burgundy Super Sport | Flickr

top506

Neil, FWIW my SS uses the Truativ adapter and a standard cup-and-cone BB with no issues.

Top

nlerner

Perhaps the tech has changed, but I remember that one or both sides of the Truvativ cups had lips of sorts, preventing me from getting a wrench on the fixed cup to tighten it down.

swampyankee2

I do happen to have access to a full machine shop, although these days I just get one of the apprentice toolmakers to do the work for me. LOL
But thanx for the clear-cut pics of the conversion process. It looks like you sourced a new crank spindle and bearing cartridge kit in addition to the adapters.

machinist42

Well then, have one of the lads fab one of these! (And two for me, if you please?) The advantage is that you will be able to use the extant cups, races and bearings, all of which are virtually indestructible.




from recently sold ebay listing.

And with cups and races:


from sold ebay listing.

And here's Schwinn's Tech Sheet on the Conversion and Item:




Alternatively, you can follow this BF member's lead?



Best of luck whichever path you take.

(I suggest you fab original spindles, and pass them on to BF SS owners on the cheap, but I may be somewhat self serving with that suggestion?)

swampyankee2

there's a bunch of operations involved the machining of that spindle. Not the sort of thing an average tool and die shop is set up for. Not to mention it's made out of possibly a 4140 or similar tough alloy and probably heat treated.
I'd gladly pay for the commercially made product.

sykerocker 

Go for it! A Super Sport was my first serious ten-speed back in 72-73, by the time I sold it, it was sporting tubular wheels and had been pretty much stripped down. Thirty five years later I built an identical one, then converted it over to cotterless bottom bracket, and a Nervar crank, as detailed above. However, the one I used (got it on Amazon) didn't use the original bottom bracket cups. Rather, you knocked the cups out and replaced them with a Fenix aluminum bracket that was held together by three Alan bolts and was threaded to use a standard English bottom bracket. It worked really well, and looked a lot less kludgy.

As to the Fenix:

https://www.amazon.com/Fenix-Bracket...ps%2C57&sr=8-5



This is the initial build, before I did the bottom bracket conversion. Unfortunately, I don't seem to have any picture of 'after'.

Jeff Wills

Thanks. That bike is an exercise in interchangeability. The crank area consists of:
Truvativ adapter rings
Shimano bottom bracket
Nervar crank arms
TA crank bolts
Velo Orange chainring
MKS pedals
and
SRAM chain

It was fun for me... an old bike mechanic who's been working on bikes for more than 40 years. It shows how fungible bikes really are... and I like to use the word "fungible",
.

Glennfordx4

They still make adapters like this, I had a bunch for both Doubles & Triples but used all of the doubles up on Schwinn builds no less and bought a new one for another Schwinn build. I have 2 triple setups left I think. The one I bought was for this Varsity that I put a set of Le Tour cranks on.

GamblerGORD53

My 1973 CCM with new SA XRD3 has a 168 mm 1Pc. It has pitting and something is not square, so I have to run it loose. I did 3 centuries on it last Sept., EASY. The crank with my new Nexus 7i is stiff as a board. WTF.
Far better than any cotter crank.

WilliamK1974

I wish these were easy to find as I wouldn't mind putting a triple chainring on my '67 Super Sport. I've just managed to get it into riding condition and am still running the Ashtabula crank. Having a lower gear would be nice with the hilly terrain in this area.

pastorbobnlnh 

WilliamK1974 a work around can be finding a suitable 74BCD chainring (or even a 30T or 32T Suntour freewheel sprocket),and drilling the needed mount holes in the steel spider and taping them to accept bolts. This could even be accomplished with a hand drill.

Hudson308 

This 136mm spindle conversion looks long enough for a triple.
Or another truly ugly option is this.

mf70

I'm pretty happy with my "upgrade" for my Sprint. I got the Truvative BSA conversion and mounted an old silver SRAM Truvative triple. Since GXP bottom brackets only use the non-drive side bearing for lateral positioning, the fact that the Schwinn's BB shell is only 55mm wide didn't make much difference. I used ~5mm of foam on the drive side instead of the wavy washer. Heh, it only saves 500g from the steel crank, though weight savings wasn't why I was doing it. The stock Schwinn front derraileur handles the triple and the chain line is perfect.

The stem shifters also were replaced with Suntour bar end units, while the Winemann brake levers left in favor of these. The broad resin frames are pretty comfy and are almost as convenient as the old suicide levers. Things look a lot tidier in the office now.

Mark