Re: [CR] Frame stiffness NOW Frames Getting Soft and 753


Example: Humor:John Pergolizzi

In-Reply-To: <AANLkTintq6dqOkU5xnaqJwBrK1hx8qdmDFV2vqRX-0ID@mail.gmail.com>
References: <AANLkTimZHYmUVd0QQzF6LYyasZOF7p46vnw8L-p95vKE@mail.gmail.com>
Date: Tue, 6 Jul 2010 12:29:44 -0700
From: Jim Merz <jameshmerz@gmail.com>
To: Harry Travis <travis.harry@gmail.com>
Cc: classicrendezvous@bikelist.org
Subject: Re: [CR] Frame stiffness NOW Frames Getting Soft and 753


753 is not a tube choice without some risk of frame failure. I was certified to build with this and did quite a few bikes in 753. First problem was the early QC was not the best, the hardness of some tubes was too high. Then, if the heat applied during assembly was over 1200F the tube would fail at that joint. As the silver melts at 1100F there is not much room for error. Very highest level of brazing skill is required. This is why Reynolds only sold sets of 753 to certified builders. But also, these 753 frames were light and one cannot expect any very light steel frame to last forever. I have to say the failures I saw were almost always at the seat stay/seat tube joint, and it was not a failure that would put you on the ground. I rode a Merz 753 frame into the mid 1980's. Finally noticed a creaking sound and found a cracked seat stay. I mentioned before about my role in Tange Prestige tubing. It is not as sensitive to heat, so is easier to build with. And, the QC was great. Some of the best steel tubes ever made for bikes in my opinion.

Jim Merz Big Sur CA

On Tue, Jul 6, 2010 at 11:50 AM, Harry Travis <travis.harry@gmail.com>wrote:
> That's a very interesting letter, providing context for that line from
> Merckx (or Hampsden) about the importance of handling.
>
> But, what does it mean that Reynolds 753 was not a long-lasting material
> [in bikes built with those tubes?
>
> Also noted, Tange Prestige, which "don't get no respect" from too many of
> us.
>
> [ I know the modern TdF is off-topic, but allowing one third or more of all
> riders to crash themselves and their bikes Sunday on a portion of the
> course
> spoiled by an motorcyclists' oil spill would seem riskier than putting them
> on frames that might have a higher failure rate, if that is what "not a
> long-lasting material" meant. ]
>
> Harry Travis
> Pine Barrens of NJ
> USA
>
>
> On Tue, Jul 6, 2010 at 11:13 AM, Angel Garcia <veronaman@gmail.com> wrote:
>
> > I haven't followed this thread closely but I thought I would re-post an
> > email from Andy Hampsten that I received in 2004 in response to a
> question
> > I
> > had about a particular bike he was riding in a stage. His reply:
> >
> > "Hi Angel,
> > Good eyes there. Eddy Merckx was and still is the master of matching
> riders
> > to frames. He would start all of us on Columbus's Max tubing for the
> > earlier
> > season races. They weighed more than other tube sets but it was a joy to
> > get
> > such responsiveness out of a frame. For my bikes Eddy would get me on
> > lighter but very strong frames for the April Ardennes races and early
> stage
> > races. By June and the important stage races I would be flying on his
> > lighter bikes with the Tour ride being a very sweet Reynolds 753 based
> > super
> > light frame ready to rocket.
> >
> > Of course a lot of riders, me included would moan about "yeah but that
> team
> > gets to ride super light carbon or aluminum" or what ever else looked
> like
> > greener grass to us. Eddy was good at pointing out to us that there was
> no
> > sense shaving ounces off of a frame and fork that would save us seconds
> on
> > the climbs but wouldn't handle well. "Why gain 40 seconds on a climb and
> > loose 2 minutes on a descent?" he would reason. Looking back to where
> those
> > materials where in the early 90s I have to agree.
> >
> > The riders where able to decide what they wanted to ride on. Of course it
> > was limited and I hate to say it but it depended on how the rider's
> > political status was with the team. Eddy took care of all the riders but
> > few
> > were spoiled with a new frame every week or two like I was.
> >
> > I really liked the 753 tube set, but Eddy knew it was not a long lasting
> > material. He let me use them for the mountainous tours and a few big one
> > day
> > races, and then put them to rest.
> >
> > In '88 I had a fantastic frame made by John Slawta of Landshark that got
> me
> > up and over the snowy Gavia pass. He used Tange Prestige tubing back
> then.
> >
> > Enjoy your ride, whatever it is. Andy Hampsten"
> >
> > Angel Garcia
> > Long Valley NJ
> >
> >
> >
> >
> > ---------- Forwarded message ----------
> > From: Jim Merz <jameshmerz@gmail.com>
> > Date: Tue, Jul 6, 2010 at 10:28 AM
> > Subject: Re: [CR] Frame stiffness; Was: Phil disk brake, Vitus 172
> > To: Jan Heine <heine94@earthlink.net>
> > Cc: JB Froke <jbfroke@mac.com>, hmsachs@verizon.net,
> > classicrendezvous@bikelist.org
> >
> >
> > My wording was not correct, you made it clear. However, a heavy, strong
> > rider using a frame made with 531SL can stress the tubes to cause early
> > failure. In this case the much higher tensile strength of 753 makes for a
> > much longer lasting frame. I agree that the ride is very nice also.
> >
> > Jim Merz
> > Big Sur CA
> >
> >
> > On Mon, Jul 5, 2010 at 9:43 PM, Jan Heine <heine94@earthlink.net> wrote:
> >
> > > At 8:06 PM -0700 7/5/10, Jim Merz wrote:
> > >
> > > frame getting "soft" from use [...] old wife's tale. The benefit from
> > >> using a very high
> > >> tensile steel such as 753 is that a strong rider can flex it quite far
> > >> without yielding it.
> > >>
> > >
> > > I have yet to see a rider strong enough to flex a frame made from 531
> to
> > > the yield point...
> > >
> > > I believe that the myth of high-end steels being stiffer came from two
> > > observations, none of which actually relate to stiffness:
> > >
> > > 1. The super high-tensile strength steels are much harder to cold-set.
> So
> > > builders often thought they were stiffer, when in fact, they just
> > required
> > > more bending until they took a set.
> > >
> > > 2. Many riders prefer flexible frames without knowing it. When asking
> > these
> > > riders, they'll often tell you that their new frame is "so stiff, it
> > > accelerates wonderfully," even though when measured, the frame is much
> > less
> > > stiff than their old one that felt "dead." So when the super-high
> tensile
> > > steel frame with ultra-thin walls "felt stiff," it contradicted the
> fact
> > > that thinner walls make a tube more flexible. The only way around this
> > > conundrum was to reason that the new super-high tensile steel must be
> > > inherently stiffer, which more than makes up for the thinner walls.
> > >
> > > We have documented in double-blind tests that more flexible frames can
> > > accelerate better for some riders. It's too involved a subject for this
> > > thread...
> > >
> > > As for frames going soft, the French never heard of that one,
> otherwise,
> > > they wouldn't have reconditioned decades-old favorite frames... I don't
> > know
> > > whether Italians believed this, so the only place where I have seen
> this
> > > concern documented is Britain, and from there, it seems to have
> migrated
> > > across the English-speaking world.
> > >
> > > Jan Heine
> > > Editor
> > > Bicycle Quarterly
> > > 2116 Western Ave.
> > > Seattle WA 98121
> > > http://www.vintagebicyclepress.com
> > > --