[CR]Re: cup and cone wear (not just on Motobecane)

(Example: Framebuilding:Norris Lockley)

From: "Reid Fisher" <reidfisher@hotmail.com>
To: classicrendezvous@bikelist.org
Date: Tue, 05 Sep 2006 17:52:29 +0000
Subject: [CR]Re: cup and cone wear (not just on Motobecane)

FWIT, the fine shiny line described has shown up on every cone and cup I've seen, and I infer it to lie early along the time line from new to burnishing to wear to pitting. Who cares how it looks, though -- how does it feel when adjusted? The cheesy cones I got once for my early-70's Normandy hubs appeared to be granular in their surface texture. I had this impression that they actually smoothed out a tad as they wore in just a bit (maybe needing some readjustment). Was that real? -- maybe my impression really was a product of some kind of period-correct haze.

You metallurgists: what's the mechanism (at the micro scale) for pitting? Does it start at some kind of micro-irregularity in the bearing where stress is concentrated?

Reid Fisher
wearing my cones in San Martin, California