Peligro en neumáticos 245 en RS2

[RS2_911C2]

Hola,

 

Puede que ya se haya tratado este tema en el foro, pero como he descubierto el foro hace poco y el tema es muy importante creo que no pasaría nada si se repite.

 

¡NO MONTES NEUMÁTICOS 245/40 EN UN RS2 SOBRE LA LLANTA ORIGINAL A NO SER QUE SEAN DUNLOP SP8000! HAY SERIO PELIGRO DE QUE EL NEUMÁTICO SE SALGA O REVIENTE CON EL CONSIGUIENTE RIESGO PARA LOS OCUPANTES DEL COCHE.

 

El RS2 venía homologado con la Dunlop SP8000 de 245/40 montada sobre una llante de 7". Esta combinación en principio no es posible pues el neumático sería demasiado ancho para la llanta, pero esta Dunlop SP8000 tenía unas características únicas que le permitía ser montada en llanta de 7": tiene los flancos poco rígidos por lo que se abonba y adapta bien a la llanta. La mayoría de neumáticos actuales son precisamente lo contrario, tienen unos flancos muy rígidos con lo que una 245/40 "normal" va muy forzada en una llanta de 7" haciendo que el neumático se desgaste fuertemente en la unión con la llanta con lo que podría reventar o salirse de la llanta en plena curva que es cuando más se fuerza esta unión.

 

Si preguntais a Audi os dirán que la 245/40 es la suya pero no tienen ni idea (en general no saben lo suficiente del RS2). Hemos hablado con Dunlop y claramente indican que NO se puede montar una 245/40 en llanta de 7".

 

Si teneis una 245/40 que no sea SP8000 montada en vuestro RS2 os recomiendo que sigais la recomendación de Dunlop y que la cambieis por 225/45 lo antes posible. Yo lo hice y el coche se incluso se comporta mejora ahora.

 

Tened en cuenta que aunque dos neumáticos diferentes digan que son de 245 no tienen necesariamente que tener una superficie de contacto idéntica y además esta nunca será de 245mm exáctamente. Además de que existen unos márgenes, la superficie de contacto depende de muchos factores como presión de inflado, temperatura, posición de la suspención (canvas), diseño del neumático, etc... Posiblemente una 225/45 moderna con unos flancos más rígidos tenga casi la misma o la misma superficie de contacto que la Dunlop SP8000.

 

Para más información os adjunto el siguiente correo de Dunlop (en Inglés)

 

From: Thomas Plehn, Product Manager CAR & 4x4, DUNLOP GmbH & Co. KG

 

I have forwarded the currently available information to Mr Wyss. Enclosed you find the status quo, as soon as we have additional information I'll let you know.

 

1. The SP Sport 8000 in 245/40 R17 was taken out of production. Currently there are apparently no plans to bring it back into production. During the next range meeting we will try to it bring back into production.

 

2. Possible alternatives: SP Sport 8080 does not work/fit, as the Audi is equipped with a 7" rim and the SP Sport 8080 is heated up to 9,3" during the production process. Max. tolerance is a difference of 1,5 ". Same problem with the SP Sport 9000: it is too wide, too (heated up to 9,0").

 

There remains the SP Sport 9000 in 225/45 ZR17, as it would fit on the rim. However we do not know in how far the vehicle's road handling is affected in a negative way. Does MOT testing make it compulsory for drivers to state modifications within the car's title (like in Germany)? The 225/45 ZR17 SP Sport 9090 is not wide enough.

 

I hope this information is useful to you.

 

Yours sincerely

 

DUNLOP GmbH & Co. KG

Thomas Plehn

Product Manager CAR & 4x4

 

====================

 

From: Stuart Wyss (Dunlop)

19/09/2002 16:09

Subject:Audi Avant RS2

 

Dear David

 

This message from Germany is not what I wanted to hear! The 245/40s in SP8000 are dimensionally different from regular tyres of the same size. They are homologation specials, ie tyres which are bespoke to the car, specially engineered to carry the load of the car at max speed , made to marginally smaller dimensions within tolerances for the size to avoid fouling against bodywork . I have discussed this with Thomas Plehn at a meeting today and he is seeing if a batch can be produced. However this may not be resolved in time for your tyre change needs. Your challenge will be to find alternative tyres which suit the tight dimensional requirements to avoid fouling when the tyres grow (ie increase in

diameter) due to centrifugal force and heat when running at high speeds. I have searched our information to try to find out with which brand (s) we shared the Original Equipment contract on this car, but without success. From memory I have an inkling it may have been Pirelli. I will revert to you as soon as I have confirmation of production. I can only apologise for this. I am determined to do all I can to rectify matters for you.

 

====================

 

Unfortunately I have not yet heard whether they will start manufacturing small batches of these tyres...

 

So it looks like you will need to modify the car documents to accept 225/45 tyres - or convince Dunlop to start making SP Sport 8000 tyres again. I am sure there must be a process for achieving that in your motor legislation, maybe you can get an official Audi dealer to confirm in writing that the only safe and acceptable 245/40 size tyres for this vehicle are no longer manufactured and the only safe tyres are now 225/45.

 

cheers

 

David

 

--- "lycos.es" <jorge.mirat.galet@lycos.es> wrote: > I thought so...

>

> One question. Those of you that live in burocratic countries how do

> you do with the homologation of the 225/45 tires. The technical

> specification from

> the manufacturer says 245/40 so fitting anything else will make the

> car to

> fail the MOT (UK), ITV (Spain) or whatever is called this basic car

> test the

> goverment does in your countries.

>

> To legally fit 225/45 I'll have to modify the "technical card" for the

> car and that is not a simple thing to do... I'l probably need a letter

> from Audi

> saying that it can be done...

>

> Comments?

>

>

> ----- Original Message -----

> From: "Ricardo Tannus" <ricardo@esferas.com.br>

> To: <RS2list@yahoogroups.com>

> Sent: Wednesday, February 05, 2003 5:08 PM

> Subject: Re: [RS2list] RS2 Tyre recommendation please!

>

>

> > Sorry!!!

> >

> > The correct is 225/45!

> >

> >

> >

>

___________________________________________________________________________

> >

> > Ricardo Tannus Fone: (11) 6192 4500

> > Esferas Software Fax: (11) 6191 2109

> > ricardo@esferas.com.br

> > www.esferas.com.br

> >

> > > From: jorge mirat galet <jorge.mirat.galet@lycos.es>

> > > Reply-To: RS2list@yahoogroups.com

> > > Date: Tue, 04 Feb 2003 11:10:19 +0100

> > > To: Ricardo Tannus <ricardo@esferas.com.br>

> > > Cc: <RS2list@yahoogroups.com>

> > > Subject: RE: Re: [RS2list] RS2 Tyre recommendation please!

> > >

> > > Ricardo,

> > >

> > > You say you have "Yokohama AVS Sport 225/40 ZR 17" is that

> correct?

> 225/40??

> > >

> > > Or is it 245/40 or even 225/45???

> > >

> > > Jorge

> > >> ------- Original Message -------

> > >>

> > >> From : Ricardo Tannus

> > >> Date : Tue, 04 Feb 2003 00:40:32 -0300

> > >>

> > >> Hi Robin!

> > >>

> > >> Where you from?

> > >>

> > >> My RS2 use Yokohama AVS Sport 225/40 ZR 17; this tire has equal

> size

> than

> > >> original rs2 dunlop

> > >>

> > >> Bye,

> > >>

> > >> Ricardo

> > >>

>

______________________________________________________________________

> > > _____

> > >>

> > >> Ricardo Tannus Fone: (11) 6192 4500

> > >> Esferas Software Fax: (11) 6191 2109

> > >> ricardo@esferas.com.br

> > >> www.esferas.com.br

> > >>

> > >>> From: "Robin Barker"

> > >>> Reply-To: RS2list@yahoogroups.com

> > >>> Date: Mon, 3 Feb 2003 21:58:40 -0000

> > >>> To:

> > >>> Subject: [RS2list] RS2 Tyre recommendation please!

> > >>>

> > >>> I am the proud owner of an immaculate RS2 in Ragussa Green with

> > >>> approx 55k miles on the clock

> > >>>

> > >>> I will shortly need a new set of tyres and understand that the

> > >>> Dunlop SP Sport 8000 (currently on my car) in the size 245/40 ZR

> > >>> 17 are specifically designed for the RS2

> > >>>

> > >>> Is it worth fitting these again or trying a more modern high

> > >>> performance tyre thinking that perhaps technology has moved on

> > >>> over the 7 years or so

> > >>>

> > >>> Any suggestions or recommendations greatly received

> > >>>

> > >>> Regards

> > >>>

> > >>> RGB

> > >>>

> > >>>

> > >>>

> > >>

> > >>

> > >> To unsubscribe from this group, send an email to:

> > >> RS2list-unsubscribe@egroups.com

> > >>

> > >>

> > >>

> > >> Your use of Yahoo! Groups is subject to

> http://docs.yahoo.com/info/terms/

> > >>

> > >>

> > >>

> > >>

> > >

> > > ______________________________________________________________

> > > Sorprende a tus amigos con magicas postales animadas. Entra en

> > > http://www.lycos.correomagico.es To unsubscribe from this group,

> > > send an email to: RS2list-unsubscribe@egroups.com

> > >

> > >

> > >

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> >

> >

> > To unsubscribe from this group, send an email to:

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> >

> >

> >

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> >

> >

> >

> >

>

>

 

=====

regards,

 

David Sidwell

(jameshunt@rocketmail.com)

[DavidRS]

Ok Jorge, tomo nota...

 

 

 

Gracias y S2