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From: (Jobst Brandt)
Subject: Re: Will My Bikes Melt?!
Date: 31 May 2000 22:17:25 GMT

Lloyd anonymous writes:

> I live in the tropics and we can get average temperatures around
> that for most of our summer, although we do have high humidity.  The
> temperature in your shed should be a fair bit cooler than outside
> bit if its not maybe just a put your stuff inside in a dark
> ventilated room.  Let your tires down and you should be fine.

What's this "ventilated room" bit?  The bicycle doesn't breathe air as
a living organism.  I see your advice is purely theoretical from your
perception of environmental effects.

> The trouble with air-conditioning is that moisture can form inside
> the tires etc with the temperature changes, this does more damage
> than dry heat.  Considering that tires can easily withstand high
> road temperatures and the added heat from braking I don't think high
> ambient temperatures will do much damage.

Maybe you can explain how this occurs.  Refrigerant air conditioners
dry air that passes over its cooling coils, condensing water on the
cooling elements to be collected in a drip pan.  Chilled air is drier
than ambient just as heated ambient air is drier in cold climates.
With an evaporative cooler (aka swamp cooler) humidity increases but
not above healthy proportions.

So what happens when you bring your hot bicycle in from a ride in the
heat?  The frame is hotter than ambient room air and cannot adsorb
moisture.  When it cools, it again does not adsorb moisture, being no
cooler than any other object in the room.  Finally, when the cooled
bicycle is taken out doors, it will not adsorb moisture because it is
hot and dry out there.

Your scenario only might conceivably apply when riding in winter,
bringing a cold bicycle indoors, something we do regularly and never
give it a thought.  Before moist warm room air can effectively diffuse
through the tiny openings into unpainted tube interiors, the frame
will have warmed up to ambient.  Condensation on the exterior finish
is certainly less damaging than one ride in the rain, but then fear
mongers abound on the net.  What do you get out of posting this drivel?

> One year training in Flagstaff, AZ I lent my bike against a shop
> window that had glazed reflective windows and my Giro helmet melted,
> all the plastic covering on the side facing the window melted.

Don't buy Giro helmets.

Jobst Brandt      <>

From: (Jobst Brandt)
Subject: Re: DAVE'S WHEELS
Date: 1 Jun 2000 15:28:33 GMT

Graeme Cameron writes:

> Why are the wheels creaking?  It's an ordinary enough rim (not a
> light one though at 500gm+), as are the hubs.

I can't hear the sound here through the text but there is a cause for
creaking clicking sounds in a wheel that has been ridden wet.  Rust on
steel eyelets that support the spoke nipples will cause clicking sounds
that can only temporarily be suppressed by a drop of oil at the
interface.  However, the sound will return if again ridden in the rain.
The rust is permanent.

Jobst Brandt      <>

From: (Jobst Brandt)
Subject: Re: Will My Bikes Melt?!
Date: 1 Jun 2000 20:22:29 GMT

Nick Maclaren writes:

>> I think you can't count question marks.  I see three questions...
>> However, you imply with your "questions" that riding in the rain,
>> something that occurs often all year, must be severely damaging to
>> steel bicycle frames, the only kind I have ridden for many years.
>> None of these frames suffered rust damage in spite of their tubes
>> being bare steel inside.

> That is because you live in a low humidity area.  The same does
> not apply everywhere.

I think you'll find that humidity is 100% when raining and shortly
thereafter regardless of climatic zone.  Your imply that everyone else
lives in an arid region where humidity never rises above 20%.  This is
a common misconception because humidity at moderate temperatures is
not uncomfortable for humans while the combination of warmth and
humidity is.  Metals do not have this perception.  Besides, I have
lived and ridden in highly humid areas, the US east coast, northern
Europe as well as the foggy coastal region near San Francisco.
Humidity was high enough in Europe to delaminate my last wood rim
wheels that warped and separated moisture, however, the steel frame of
my bicycle showed no ill effects.

> Frames FAIL in the UK from internal rust - not quickly, but after
> decades.  Until recently, MOST UK cars ceased to be roadworthy
> because of condensation INSIDE the subframe members causing rust.
> The FIRST symptom was a rust hole appearing from the inside,
> often while the external paint was intact.  Yes, really.

I don't believe a word of it.  Cars fail from corrosive deicing on
roads long before anything rusts in the passenger compartment.  TO
what sort of antiques are you referring?  There are plenty of old
timers that were not driven in winter and they survive excellently.
It is San Francisco cars that rust from the top down, but not from
humidity but rather from salt spray from the sea.  That's why there
are no giant redwoods in the city; they don't grow in salty fog.

> I have absolutely no idea if the various gimmicks work, but assume
> that they do.  Simple grease works well enough, as can be seen by
> the rust line often stopping where the bottom bracket grease begins.
> The gimmicks probably work by delivering the grease to the more
> inaccessible parts.

I don't believe you have cause and effect linked.  There are enough
bicycles, cars and railway carriages to prove otherwise.

Jobst Brandt      <>

From: (Jobst Brandt)
Subject: Re: Very Lucky (Synchros) break
Date: 4 Aug 2000 21:18:49 GMT

Brian Lafferty writes:

> And Euro bicycle makers used to hammer a piece of wood up into the steerer
> tube to ease the failure if the steerer tube broke, as it often did, on
> shitty Euro roads.  Both of my PX10LEs had them hammered up there.

This and other urban legends abound.  Roads in Europe are no worse
than elsewhere and a wooden plug only enhances the probability of
failure because moisture collects between wood and tubing.  Those who
have had a bicycle where the paint shop failed to remove the paper
plug in the seat tube know how that works.  The paint begins to
wrinkle, there where the clump of wet newspaper is stuck and then it

Jobst Brandt      <>

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