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Salut à tous,
Je sais que quelqu'uns ici vont dire " oh non pas lui avec son Put' de magnésium !!" Wink
Voilà la réponse que je vous livre brute, des questions que j'ai posées chez MARVIC.
aah oui! c'est en Anglais, mais dès que j'ai le temps, je ferais une traduction s'il y a de la demande.
S a M
LA QUESTION
-----Messaggio originale-----
Da: Samuel Jager
Inviato: lunedì 21 novembre 2005 10.57
A: info@marvic.it
Oggetto: Aging of magnesium
Hello,
In the first place, i'd like to apologize for not writing in
italian, and i guess you'll excuse my poor english.
But this as very little to do with magnesium and Marvic, so back
to our subject. As you probably know urban legend have a long and
tough life.
As many ducati owners, Marvic is part of the legendary equipment
of a well prepared racing machine, or an achieved road bike. So
Marvic is frequently in our discussion. But there is a point coming
up in such discussion.
Magnésium is very fragile to shocks, as a life duration, micro-
cracks may appear and when, on old whells ( the usual age limit is
situated between 8 and 10 years ), the paint cracks those microcracks
are making the water to get inside the structure of the matérial
and ... well! this is the end!
An other point is that magnesium is not a material to be used on
bad roads, the only place for it is the track. An old magnesium whell
could exploded on a pothole...etc
I could have written a whole page of these sentences. Every one is
aware of the extraordinary changes due to ultra rigid and light
whells but ...
I hope you can answer to those preoccupations.
As an example, the 900 SS Superlight has been in it's first
version ( 1991...) equiped with three parts wheels. And one of this
part is a Marvic magnesium hub. What could be done to ensure the
safety of the machine and the pilot?
An other question, new magnesium whells have to be maintained, i
guess. could you explain how ?
Thank you for reading that mail, hoping to read you back.
Samuel
ps: if there's a facility to write in italian, don't hesitate, i can
have it translated ( you bet there some italian speaking ducati fans
here in belgium )
LA REPONSE
Dear Samuel,
first of all we would like to thank you for your kind words, and
good speaking about our company.
In Europe magnesium wheels have no homologation for street use ( nor our
wheels neither
our competitor's wheels !! ) because of the corrosions problem.
As regards strength of the wheels there are no problems: for our new models
of wheels
we have simulated all the strength TUV tests. And as regards Penta or Piuma
wheels
they have JWL homologation for street use.
But most of the wheels we sold ( for example in Italy more than 70% ) are
also for street use.
Without problems. Even because it is possible to repair them in case of
little crashes.
Safety is the most important thing for us, and we can say that we can grant
it to our customers, even for street use.
Obviously magnesium wheels need special handling, "special care":
after a little crash a check is needed. Fitting tyres the highest attention
is required.
At the end of the season wheels have to be dry and also checked ( by the
owner ).
It is enough to watch them carefully: if little cracks, or little problems
with the paint
are eraised ( if you see magnesium alloy, in silver colour ) a check by us
is needed.
Cleaning the bike and wheels no aggressive soap have to be used ( only
alcohol free soaps ).
But this little "attentions" will be enough.
Also the holes ( bolts holes ) have to be checked. They always have to be
circular!
We are also ready to check some pictures, if you want to have our
suggestions.
Usually we give warranty of about two years about our wheels, and then we
ask to our customers to send back wheels
to us for testing ( X-ray, penetrating liquids, pressure test and so on ).
If everything with these tests is ok, we can change paint, re-painting the
wheels and changing all the assembling kit.
Sometimes we have tested wheels after 10 or 12 years, and they are still in
good condition.
If you want you can send us the magnesium hubs for testing, but please take
note that
they are very old, and that we can not give an other warranty about them.
If we will give back the hubs to you, is because we are sure about safety,
but then also rims, and
all the other parts ( bolts, nuts and so on ) have to be tested.
We have stopped production of these kind of wheels more than ten years ago,
and as you can imagine
they can not be eternal. Usually we check and re-paint these old parts, but
we ask to our customers to keep the bike as
something like a "shrine", only for "show" or exhibition! As you can
understand our quality standards have increased a lot since '80s....
I hope that these explanations will be enough for you and your friends.
If you need more information, do not hesitate to contact me.
Kindest regards,
Silvia Framba
MARVIC WHEELS
Pour moi c'est assez clair, mais bon je lis l'anglais
la suite de ce post historique :
http://www.planete-ducati.com/site/index.php?option=com_jfusion&Itemid=5&topic=12604.0
