Your Bike is Obsolete

On 11/22/2019 3:15 PM, Tim McNamara wrote:
In the interests of
full disclosure, I'm a fat guy on a bike too. Mine just look vintage instead of modern.

Perhaps it's just personal taste, but I think fat (or fattish) old guys
on bikes look better on vintage bikes. I'm told I'm not fat, but I
choose those bikes as a precaution.

--
- Frank Krygowski

On 11/22/2019 3:31 PM, Tim McNamara wrote:
On Wed, 20 Nov 2019 11:14:23 +0100, Ned Mantei wrote:

Sheldon Brown had (and used)a 63-speed bike-- 3 chainwheels, 7 cogs, and a Sturmey-Archer 3-speed hub.
See https://www.sheldonbrown.com/org/otb.html .

Damn, I miss Sheldon.

+1


--
- Frank Krygowski

On Friday, November 15, 2019 at 10:40:45 AM UTC-6, Tom Kunich wrote:

But the closing of bicycle shops all over the bay area is a clear sign that manufacturers are killing themselves.

Hmmm. Did the closing of Radio Shack indicate computers and all electronic things were dead? You seem to imply that with this foolish statement. Now I will grant you that Commodore died out. And IBM died/changed its nature. But it seems to me we are almost overrun with the electronic stuff Radio Shack represented.

On Sunday, November 17, 2019 at 8:36:18 PM UTC-6, Sir Ridesalot wrote:

I'm 68 now and I feel I have enough stuff to keep my Uniglide equipped bicycles going even after I go to the Great Bicycling Paradise in the Sky.



Will that Bicycling Paradise have separate, divided bike paths? Or just bike paths designated by white paint on the road? Or will the bicycles be expected to ride right in amongst the cars up their in Paradise?

On Sunday, November 17, 2019 at 10:14:42 PM UTC-6, jbeattie wrote:

because even sexed-up, 12sp Di2 with discs and the latest shiny things are not selling.


I wonder if the fact those bikes cost $11,000 USA dollars might also, maybe be a reason they are not selling.

On 11/22/2019 2:45 PM, Tom Kunich wrote:
On Friday, November 22, 2019 at 12:15:46 PM UTC-8, Tim McNamara wrote:
On Mon, 18 Nov 2019 10:42:25 -0800 (PST), Tom Kunich wrote:
On Monday, November 18, 2019 at 9:33:40 AM UTC-8, AMuzi wrote:
On 11/18/2019 11:13 AM, Frank Krygowski wrote:

Our bike club hosted a speaker a few days ago, a PhD chemist and bike racer who talked about cross
linking, about carbon fiber frames, etc.

At one point, she claimed that CF frames lose something like 10% of their strength in 10 years due
to the effects of sunlight and water.

I'm not a big fan of CF, but I'm skeptical of that, at least until someone shows me good data.


Isn't that sort of scaremongering usually phrased as , "Could possibly" or "may under some
conditions" ?

One datum: My salvage Kestrel 200 fixie shows no deterioration after 25 half-seasons of foul weather
abuse in salt and abrasive crud. Notably, there are no rust bubbles typical to steel frames similarly
punished.

Because of the large variations in use, aging of the resin, how much time in sunlight and the
particular resins used the actual failure rates are pretty low. So you can't use one example as a
measurement of time to failure.

Seems like the catastrophic failure rate of CF frames is improved, at least as ar as reports of JRA
failures goes. There is still some proneness to fracturing in a crash, such as breaking the top and
down tubes, but that too seems reduced. The Busted Carbon blog hasn't had an update since 2011,
although that's only evidence that the blogger stopped updating.

My expectation has been that manufacturers would improve materials and techniques resulting in much
reduced failures. Perhaps that has happened while I wasn't looking; I haven't opened a modern bike
publication in probably 10, and even that was Bicycle Quarterly back when I subscribed (and that seems
to be all about mountain bikes styled like road bikes, these days- shades of Charlie Cunningham and
Jacquie Phalen. Everything new is old again or something like that). I don't know about other places,
but CF bikes around here are very much in the minority. I mainly only see them under racers and 50 year
old guys with big bellies and undersized jerseys. Sorry for that mental image. In the interests of
full disclosure, I'm a fat guy on a bike too. Mine just look vintage instead of modern.

They just had a catastrophic fork failure in the Tour or Poland though I haven't been able to get any derails. Hopefully without serious injury.

I think that there is a two pronged reason for the reductions in failures, 1. The engineering of the new "aero" frames spreads the loads far more better and helps to have far less new bike failures and 2. Because of the appearance of the new aero frames the majority of bikes are now relatively new.

Since Colnago and Pinaello in Europe only offer a 2 year warranty while Trek (and I assume Specialized) offer lifetime limited warranties there are questions raised about just how safe the material is. How much of this is CYA and how much is it American manufacturers relying on changing designs so that the original owners sell them off and relieve Trek etc. from financial liability.

Jay might have a better idea of this. Does Trek retain much liability for a broken frame since the company can always claim that it was abused before second hand sale?


I don't think his fork caused this year's crash:
https://www.ridemedia.com.au/feature...chts-accident/

And whatever Trek's warranty policy might be, those aren't
USA material or manufacture.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Friday, November 22, 2019 at 2:06:58 PM UTC-8, wrote:
On Sunday, November 17, 2019 at 8:36:18 PM UTC-6, Sir Ridesalot wrote:

I'm 68 now and I feel I have enough stuff to keep my Uniglide equipped bicycles going even after I go to the Great Bicycling Paradise in the Sky.



Will that Bicycling Paradise have separate, divided bike paths? Or just bike paths designated by white paint on the road? Or will the bicycles be expected to ride right in amongst the cars up their in Paradise?

Remember that the people who take a close pass at you either through ignorance or purposefully are not going to be there. So you don't need bike lanes.. Most of my rides are over roads that do not contain bike lanes and drivers are invariably polite save for the few damned.

On Tuesday, November 19, 2019 at 4:19:38 PM UTC, sms wrote:

Once you paint it [carbon fiber] you're shielding it
from UV light, at least partially...

....and progressively less and less. There's rarely a time when I don't have some paints up in my studio window to study the effect of UV on their pigments. All paints are just ground (milled) pigments in a more or less clear setting medium which can be anything from honey to drying oils (linseed oil etc) to resins. Everyone uses the same pigments; when a pigment for artists goes out of supply, it is usually because automobile manufacturers no longwe want it (when gold cars stopped being popular, quinacridone gold PV49 suddenly disappeared from colourmen's lists), or because they suddenly want too much of it and a shortage develops and artists suck the hind tit. Pigment lightfastness is rated according to the Blue Wool Scale of 8 steps, in which ratings of BWS 7 or 8 are considered permanently lightfast if carefully hung, and 6 is often said to be good for a 100 years under normal display, meaning not in direct sunlight. Conscientious artists stick to pigments with ratings of 7 or 8. No pigment is totally lightfast under all conditions: the most common compromising factors are mixing pigments to achieve colours not found in nature, or natural colours not matched by any pigment, or to match pigments that are too expensive (the cobalts PB35 etc), unsympathetic catalysts of the setting or emulsification or other processes in which the paint is dried and bonds with the media on which it is painted and on the air-side forms a protective layer, a long, long list. Some pigments are shockingly shortlived but are used by irresponsible traditionalists anyway, such as alizarin crimson PR83. The upshot is that no paint will protect your carbon bike forever, because the pigment will lose its effectiveness in keeping out the UV, and then all that protects the fibres or their holding matrix is the normally clear alkyd or whatever normally clear liquid carried the pigment. Claiming that paint will protect a carbon fibre bike should be a strictly time-limited argument, like: "If you want the protection of paint on your carbon fibre bike, you'd better repaint it every four or five years." Just to hammer the point home, alizarin crimson PR83, a very taste bike colour, in sunshine will fade to almost nothing in a couple of months. A good, permanent cover for carbon fibre is gold plating, but of course a gold-plated bike will have to be totally scrapped on some conservative precautionary schedule because you will no longer be able to observe hairline cracks under the gold.

If you really want to do your nut, you can read up about pigments on Bruce McEvoy's Handprinted site https://www.handprint.com/HP/WCL/waterfs.html ; McEvoy is the most influential painter of the early 21st century not so much for the prizes he's won but for the obsessively clear logic he brought to the profession and its materials. Before that he was the scientific end of reprographics, as I was the aesthetic end, so he knows his oats.

Andre Jute
Weird and wonderful knowledge dispensed

On Friday, November 22, 2019 at 5:06:58 PM UTC-5, wrote:
On Sunday, November 17, 2019 at 8:36:18 PM UTC-6, Sir Ridesalot wrote:

I'm 68 now and I feel I have enough stuff to keep my Uniglide equipped bicycles going even after I go to the Great Bicycling Paradise in the Sky.



Will that Bicycling Paradise have separate, divided bike paths? Or just bike paths designated by white paint on the road? Or will the bicycles be expected to ride right in amongst the cars up their in Paradise?

Easy! There won't be any cars.

- Frank Krygowski

On Friday, 22 November 2019 20:15:46 UTC, Tim McNamara wrote:

Seems like the catastrophic failure rate of CF frames is improved, at least as ar as reports of JRA
failures goes. There is still some proneness to fracturing in a crash, such as breaking the top and
down tubes, but that too seems reduced. The Busted Carbon blog hasn't had an update since 2011,
although that's only evidence that the blogger stopped updating.

An interesting YouTube channel to watch is Luescher Technik. He makes CF frames himself and often makes videos where he cuts popular frames in half, I do mean lengthwise, and points out all the voids, defects and other crap in them. He may have a slightly jaded perspective as I think he spends his free time as an expert witness in trials where people are suing Big Carbon to complain about how dead they are, but he seems to know what he's talking about.

Many of the frames are fine, and it's common in the bike industry to use slightly janky CF but make it a bit thicker as it's still going to end up lighter than a metal bike. A few high-end CF frames are made to proper "aerospace" standards.

Steel frames can fail too. I don't know the comparative rates but the much more ductile failure mode does mean you are much more likely to avoid injury if/when it does happen.