Fwd: Re: [CR]Re: Bar repair


Example: Bike Shops:R.E.W. Reynolds

Date: Fri, 9 Nov 2007 15:28:25 -0800 (PST)
From: Art Link <artlink@columnssanantonio.com>
Subject: Fwd: Re: [CR]Re: Bar repair
To: classic rendezvous <classicrendezvous@bikelist.org>


Why screw with this at all???!!*** Throw it out and buy another on Ebay. Your safety and health is worth something more than saving the handlebar(unless it came off the Pope's gold plated Colnago). This is like repairing your foam core helmet after a crash to save a few bucks. Toss it.!! Art-lost an eye in a bike crash in 1973-Link,San Antonio,TX,USA

David Snyder <dddd@pacbell.net> wrote: From: "David Snyder" <dddd@pacbell.net> To: "Classic Rendezvous" <classicrendezvous@bikelist.org> Subject: Re: [CR]Re: Bar repair Date: Fri, 9 Nov 2007 15:21:47 -0800

Aldo is completely correct on both points.

In particular, most bar's bends create twisting forces going into the clamp, and relatively long, slender glued or pressed joints do not fare well in torsion. These junctions fail starting at one end, and the failure progresses along the length to complete failure, due to the twisting that occurs along the length of tubing. I wouldn't count on the outer sleeve twisting along with the inner bar, since the stress on the adhesive will be localized at the outermost points of the bond (left and right in this case). Nor would I assume that any adhesive won't leave large areas un-bonded where air can become trapped, surrounded by glue.

David Snyder, BSME theorizing in Auburn, CA, usa

Aldo Ross wrote:


> I've tried drilling & pinning (one pin 1/8" dia) through the
> sleeve and bar, but the aluminum (non-heat-treated Cinelli
> bars) is so soft that the slippage continued, while the pin
> just gouged a slot through the bar and the sleeve.
>
> If you try glue or epoxy, remember that under load it could
> shear (break loose) at any time.