Re: [CR] (CR) It seams so unbelievable

(Example: Events:Cirque du Cyclisme:2004)

From: "Ted Ernst" <ternst1@cox.net>
To: "Mark Bulgier" <Mark@bulgier.net>, "Otis Greer" <ogreer@bellsouth.net>, <classicrendezvous@bikelist.org>
References: <81CC8569759D49DDB63FF06F14CB8CCD@GREER> <9327C3B25BD3C34A8DBC26145D88A9071732AA@hippy.home.here>
Date: Thu, 24 Jun 2010 22:02:14 -0700
Subject: Re: [CR] (CR) It seams so unbelievable


I suspect your seat tube is not DB either.
Ted Ernst
Palos Verdes Estates
CA USA


----- Original Message -----
From: Mark Bulgier
To: Otis Greer
Sent: Thursday, June 24, 2010 9:48 PM
Subject: Re: [CR] (CR) It seams so unbelievable



>
> Dickey Greer wrote:
>
>> It doesn't bother me that the head tube and steer tube are not db
>> 531. These are 2 tubes that you don't want any flex at all.
>
> No Reynolds 531 head tubes or steerers were ever DB. (A DB head tube can
> be approximated by starting with a thick one and relieving the center,
> leaving it thick at the ends, but that's only done for lugless frames --
> and extremely rare in the CR time period)
>
> A 531 head tube is plain gauge, and typically the same
> weight/thickness/stiffness as the welded item or pretty close. Head
> tubes have to fit lugs on the outside diameter and headsets on the
> inside, so they hardly vary at all in thickness from one brand of tube
> to the next. The reason 531 is better than a seamed one is strength and
> fatigue endurance -- the cheap one is more likely to crack in use.
> There is no advantage to the cheap steerer other than cost.
>
> A 531 steerer is the same weight/thickness/stiffness as the cheap item
> for most of its length. Again, the steerer has to fit the headset on
> the outside and the stem on the inside, so there's no room for making
> them any thicker or thinner. 531 is butted (heavier) at the bottom
> where bending and fatigue cracks are most likely. The cheaper steerer
> may be sleeved at the bottom to approximate the advantage of a real
> butt, but it won't be better than a real butt in any way I can imagine,
> other than cost, and will almost certainly be weaker.
>
>> I do have an all 531db TREK bike that has a Tange fork
>> from the factory. The Yellow Jersey in Madison, who used
>> to be a top Trek Dealer said that was normal.
>
> If the tube decal says "Guaranteed built with Reynolds 531 butted tubes,
> forks and stays", and it came from the factory with a Tange fork, well
> that may be considered "normal" by some, but it is FRAUD. Tange made
> good tubing, nothing wrong with it, but if Trek said it was Reynolds,
> then they lied.
>
> Mark Bulgier
> Seattle, WA USA