Re: [CR]"Three arm" brake caliper?

(Example: Framebuilders:Norman Taylor)

Date: Wed, 24 Sep 2008 15:42:01 -0700 (PDT)
From: "david snyder" <dddd@pacbell.net>
Subject: Re: [CR]"Three arm" brake caliper?
To: Classic Rendezvous <classicrendezvous@bikelist.org>
In-Reply-To: <797926.96225.qm@web82204.mail.mud.yahoo.com>


The fancier one is originally fitted to my (~1982/3) Bridgestone "Triathl on AL" with it's 1982 Suntour derailers. The bike btw is no more of a tri /multisport bike than their later 500 model, just a road bike with entire ly standard geometry. It has clear anodized arms, perhaps not quite GranCompe level finis h, and yes, it has the QR of the style found on DiaCompe G-model calipers, not too fancy at all.

David Snyder Auburn, CA

Jerry Moos wrote:

I take it the one in the photo is the less expensive version then?  Did t he better one have a QR and/or a fancier barrel adjuster?  Were these int roduced within the CR timeline?


--- On Wed, 9/24/08, david snyder wrote:


That caliper is a DiaCompe SC (self-centering). These were common on (exclusive to?) Bridgestone bikes.

There were two levels of finish for these calipers, which were paired with

non-aero DiaCompe levers. I've had both versions, and they always lacke d power with standard pads.

The hump houses a rocker link, which pivots in the "3rd arm" and is "socket ed" into the main arms.  The "3rd arm" is not really an arm, but rath er just a lever that is friction-coupled to the center bolt.  The hidden

rocker link is somewhat fragile plastic, somewhat resembling a 3-ball s egment of a bead chain, although is is quite rigid. The whole mechanism makes caliper centering fully automatic whenever the

brake is applied, which re-centers the "3rd arm" between the 2 real arms.

David Snyder Auburn, CA  usa

Jerry Moos wrote:  I would speculate it is a mid-priced mod el because of the simple adjusting barrel