Re: [CR] cottered alloy cranks


Example: Framebuilding:Brazing Technique
From: "David Feldman" <feldmans1@earthlink.net>
To: "Mark Bulgier" <mark@bulgier.net>, <classicrendezvous@bikelist.org>
References: <C102531FB711D411B5B90060B0A468760DB031@mail.bulgier.net>
Subject: Re: [CR] cottered alloy cranks
Date: Sat, 21 Dec 2002 17:18:43 -0600

Phil Wood has and still will make bb's with the pear-shaped spindle for those cranks--talk about taking care of a niche market!
David Feldman
Vancouver, WA


----- Original Message -----
From: Mark Bulgier
To: classicrendezvous@bikelist.org
Sent: Saturday, December 21, 2002 3:27 PM
Subject: RE: [CR] cottered alloy cranks



>
> Stevan Thomas wrote
> (re cottered alloy cranks)
>
> > I believe T.A. made a set like that.
>
> The TA 1500 is often called a cottered crank and I don't mind that
> terminology, but it should be pointed out that they are fundamentally
> different from cottered cranks in that the "cotter" (really a pinch bolt)
> doesn't take any of the pedaling forces. The unique pie-shaped axle-crank
> interface is pretty much rideable with the cotters out, except the arms can
> drift side-to-side.
>
> The precision of the fit between the axle and crank is amazing - this must
> be one reason they stopped making them; it can't be easy to maintain such
> tolerances. Any cottered crank is quite crude by comparison. Loosen one
> allen-head bolt and the crank slides off! You don't have to take the cotter
> all the way out, just loosen it, if you file a little catch off the end of
> the axle as I did on mine. (The catch would keep the crank from falling off
> if the bolt were loose, but it would have to drift so far before it fell off
> that you would notice it in time unless you were very oblivious - and these
> bolts don't loosen up.)
>
> For pictures and good explanations check out Joel Metz's site,
> http://www.blackbirdsf.org/magpie/ta/ref1500.html

>

> Mark Bulgier

> Seattle, Wa

> USA