[CR] summary on black rim introduction date

(Example: Framebuilders:Dario Pegoretti)

Date: Tue, 8 Sep 2009 20:14:20 -0400
From: "Harvey Sachs" <hmsachs@verizon.net>
To: Classic Rendezvous <classicrendezvous@bikelist.org>, Geof Gee <geofgee@gmail.com>, "hmsachs >> Harvey Sachs" <hmsachs@verizon.net>
Subject: [CR] summary on black rim introduction date


Thanks to all who thought about this question. Here's what I've gleaned:

From: brad stockwell offered two data points: ? 1) The first time I ever?saw black rims that could be purchased by just-plain-Joes was in a Bicycling! review of a Ciocc, it was probably early 80's but I'll have to check when I get home.? I think the brand name was Ambrosio Durex and the article referred to them as "ceramic coated" rims which were alleged by the manufacturer to be?stronger than normal rims, and that, as a?piece of optional equipment?they added $100 to the cost of the bike.?? ? Of course, I suppose 'ceramic coated' could be said of?just about any?aluminum which has?been exposed to air and formed an oxide layer.?? ? 2) In historical hindsight, though, it turns out that I also have a photo of Lucien Van Impe from the 1976 Tour which shows black rims.? ++++++++++++++++++++++++ Chas. Colerich wrote (off-list):

The first question would be, when where anodized aluminum rims first commercially available. I think that the first colored rims were "gold anodized".

The black and all other colors are dyes applied to the porous anodized aluminum surface which is then sealed to protect the dyes from deteriorating.

Aluminum anodizing is a layer of aluminum oxide that is electrochemically created on the metal surface. So called clear anodizing is a very thin layer of aluminum oxide which provides a hard protective surface on the soft aluminum. Hard anodizing provides a much thicker layer that can be up to .005" (0.13mm)in thickness. It's usually a dark gray or brown color.

The instant a pure clean aluminum surface is exposed to the atmosphere it starts to corrode forming a layer of relatively inert aluminum oxide. This is what gives aluminum it's corrosion resistance.

Pure aluminum is a soft relatively weak metal. For most commercial uses aluminum is alloyed with small amounts of other metals such as copper, zinc, magnesium, manganese and so on. The alloys increase the strength and hardness.

Aluminum alloys are not as corrosion resistant as pure aluminum so they are frequently anodized for both practical and cosmetic reasons.

I have a pair of black anodized Super Champion Arc-en-Ciel rims so they were available before the Wolber acquisition, when ever that took place. ++++++++++++++++++++++++++++++++++++ Robert Clair wrote (off-list): ... the tek 2000 was the first full bike that i saw at the lbs that came with black matrix rims when it came out summer of 1985. but the first nos black rims that caught my interest were reviewed in bicycle guide i think in late 1983/early 1984. ++++++++++++++++++++++++++++++ My question was in the context of the A-D Vent Noir, with its early D-A black gruppo. Greg Honn wrote: I worked with Steyr at that time. The product manager just never thought to order black rims. [This would push availability back into the mid-1970s, I think.]

Thanks to all, and that's all the news from Lake Wobegone.

harvey sachs
mcLean va