[CR] Re: Fillet-Brazed Schwinns - Ashtabula cranks

(Example: Framebuilding:Technology)

Date: Thu, 05 Jun 2008 07:22:14 -0400
Subject: [CR] Re: Fillet-Brazed Schwinns - Ashtabula cranks
From: "Doug Fattic" <fatticbicycles@qtm.net>
To: <hsachs@alumni.rice.edu>, Rod <rodk3d@comcast.net>, Jerome & Elizabeth Moos <jerrymoos@sbcglobal.net>, 'Classic Rendevous' <classicrendezvous@bikelist.org>
In-Reply-To: <48477855.7030900@verizon.net>


Harvey,

I was under the impression that the Ashtabula cranks on my earlier Super Sport models were made by Huret. In any case, they are made in a superior way. The arms are not round but rather have a triangular shape. They are not light but very nice to work on. That is the thing I have always liked about Chicago Schwinns. They can be a Goodwill find and abused but since many of the parts are steel, they can be cleaned up and they still look good and work fine. The Super Sport was just a nicer model of this heavy stuff.

These are the bikes that should be in third world countries. I was in a very out-of-the-way town on our annual Ukraine bike ride and there, in the lobby of a museum, was a Schwinn Continental. It was someone's transportation. All the original parts were there and working fine. It was a early to mid 70's model.

In Portland at the NAHBS this year I went to a bicycle recycling shop with Dale Brown and Co. I spent the evening trying to talk a commuter out of his 1964 Sport Tourer. That model had an Ashtabula triple crank. He has been using it for years putting thousands of miles on it as his regular commuter. He says he sees another commuter on one too. Is it a light bike? No. Can they last just about forever. Probably. That is there beauty.

Rod,

The bottom bracket shell of an Ashtabula crank is large - about twice the size of a normal one. It is possible to convert them into a standard English one but that spoils the design and intent of these bicycles. Every part seems to work together to create the whole. If you want lightness in a bike, you should get something else. These conversion kits are still available from wholesale dealer supply distributors.

Jerry,

Paramounts were made out of 19/21 gauge 531. That is about the equivalent of Columbus SP with its 1/7/1mm wall thickness. That is the heaviest normal tubing was made. Schwinn was well known for its guarantee and supported it by making frames strong, not light. For a small guy like me, it is too thick. I use 7/4/7mm non oversize tubing on my own frames.

Doug Fattic looking forward to seeing you in VA Niles, Michigan, USA

On 6/5/08 1:23 AM, "Harvey Sachs" <hmsachs@verizon.net> wrote:
> Doug Fattic wrote, but I <snip> to get to the cranks stuff:
>
> That said, the 1 piece steel Ashtabula crank makes them heavy. They
> have a kind of solid, steady feel. It is what I would use on a 3 to 5
> mile commute where I would go at a slower pace. I remember helping a
> pastor in the bike boom of 1971 get a Super Sport. He loved it and
> decided bicycling was worth investing in as a hobby. <snip>
>
> I did my first century ride on my Super Sport in 1966 in Vermont down
> highway 110 (and other roads). So you can see I like them because they
> bring back memories from when I was young and because they are nicely made
> to work on. Take away the emotion and they are kind of heavy clunkers.
>
> +++++++++++++++++++++++++++++++++++
> Couple of notes about the Ashtabula (one-piece) cranks.
> 1) I believe that the Super Sport got a better grade of crank than the
> lowly Continental-Varsity-Suburban-Collegiate models. Looks different.
> FWIW, I never bent one of the better ones, but didn't ever crash one,
> either.
> 2) Ashtabulas are just a dream to work on, once you understand them.
> Huge bearings, in retainers, set up quickly, etc.
> 3) the bolt circle, if I recall correctly, was very close to Nervar and
> perhaps others. It was possible to upgrade the rings with judicious use
> of a file here or there. Because of the generous clearance to the
> outside, I once set up a (Twinn tandem) with 4 cogs on an Ashtabula -
> three to the back and the fourth for same-side transfer.
> 4) If all else fails, conversion units are available, via BMX sources,
> to convert Ashtabula BB to tapered cotterless cranks. I've done this
> once, I think, and have some spare parts around for kicks.
> 5) The top fillet-brazed Schwinn that I remember, the Sports Tourer (aka
> Sport Tractor) used a conventional English-cup BB, with TA (or Nervar?)
> cotterless cranks.
>
> Your mileage may vary, mine will be at Cirque.
>
> harvey sachs
> mcLean va
> (and just back from riding on the American River Parkway in Sacramento)