Re: [CR] Cone Failure Causes

(Example: Framebuilding:Tubing)

Date: Sun, 22 Nov 2009 05:33:18 -0800
From: "verktyg" <>
To: <>, <>
References: <>
Subject: Re: [CR] Cone Failure Causes

Interesting idea.

Worked on a lot of Normandy hubs during the 70s. Except for the Luxe Competition models the cones for the standard Normandy/Atoms appeared to have been machined then case hardened without being ground after hardening.

Frequently saw cones in new Normandy/Atom hubs and also new replacement cones with pits in the ball track area which caused a rough spot when trying to adjust the hubs. We'd buy Normandy replacement cones in 50 or 100 pack bags. Sometimes had to use or reuse imperfect cones when good replacements weren't available.

I attributed Normandy cone failure to improper adjustment, lack of lubrication, dirt plus poor quality workmanship to begin with (shallow, uneven case hardening plus pitted ball races when new). The pressed in cups seemed to have been a little better quality.

Normandy/Atom hubs were cheap mass produced components; millions were made during the bike boom era. I don't think that they were expected to last more than a few years much less 30 to 40 years. At that time labor costs were much lower too so they were designed to be regularly repaired.

We sold replacement wheels with Rigida steel rims and Normandy hubs for ridiculously low prices. Alloy rimmed wheels where just a few dollars more. Many times with bent rims or badly worn hubs it was cheaper to sell a customer a new wheel.

I have several old bikes with Normandy hubs. I've put off servicing them because I know what the innards are going to look like when I open them up... it's not a pretty sight! ;-)

Your suggestion about rotating the rear axles is probably not a bad idea for any make hub.

Chas. Colerich Oakland, CA USA wrote:
> Just an observation and theory (not original I'm sure): After several
> recent Normandy hub rebuilds, in all cases, I found much greater damage to
> freewheel-side cone than anywhere else (otherside cone or hub races)...probably
> due to unsupported lever-effect.
> More to my point (which I'm getting to), I also found, in most cases, the
> freewheel-side cone to be brinnelled, spalled, or otherwise pitted at a
> single location along the cone race. I theorize that because the cone does not
> rotate (like hub races) a single (downward-side) point on the cone takes the
> maximum load...all of the time! I guess some would argue that a "properly"
> adjusted and lubricated cup/cone minimizes this effect. I'd buy that...but
> minimize does not equate to eliminate.
> So how to further minimize and/or prevent this damage? How 'bout rotating
> axle (w/cones) periodically? Easy enough to do but how often? I'll leave
> that to your discretion.
> Except for this disclaimer, the foregoing proposal ignores that present-day
> riders may be 50 or more lbs heavier than what designers envisioned, along
> with other contributing factors.
> Jack Romans
> Sacramento, California