Interesting? Footnote about Michelin XAS Tires

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Edwin Ek
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Interesting? Footnote about Michelin XAS Tires

#1 Post by Edwin Ek »

I saw my '62 car yesterday, which has been in storage for over two decades. My spare is an old Michelin XAS tire, in the width 180, not the familiar 185. Who knew?

Nowadays, doesn't every width end in 5?
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Pascal Giai
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Re: Interesting? Footnote about Michelin XAS Tires

#2 Post by Pascal Giai »

Michelin XAS are 180HR15
Michelin XVS are 185HR15 or 185VR15

I use 165HR15 on all my 356s with 4.5" rims. They need 2.2kg pressure to work well...

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Martin Benade
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Re: Interesting? Footnote about Michelin XAS Tires

#3 Post by Martin Benade »

Maybe 2.2 bar? not 2.2 kg
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Pascal Giai
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Re: Interesting? Footnote about Michelin XAS Tires

#4 Post by Pascal Giai »

2.2kg brings stability at speed...

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Martin Benade
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Re: Interesting? Footnote about Michelin XAS Tires

#5 Post by Martin Benade »

I was thinking you meant 2.2kg per some unit of area, which I took to be per square inch. I realize now that of course it was not an inch, but what is the common metric way to express it?
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Edwin Ek
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Re: Interesting? Footnote about Michelin XAS Tires

#6 Post by Edwin Ek »

Well, I did now what I should have done before posting. I checked. The XAS tire currently comes in 180 size. 2 lessons learned, eh?
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Albert Tiedemann
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Re: Interesting? Footnote about Michelin XAS Tires

#7 Post by Albert Tiedemann »

Martin Benade wrote:I was thinking you meant 2.2kg per some unit of area, which I took to be per square inch. I realize now that of course it was not an inch, but what is the common metric way to express it?
You need something about 30 psi.

2.2 kg [force]/cm squared would get you close.
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David Jones
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Re: Interesting? Footnote about Michelin XAS Tires

#8 Post by David Jones »

Actually 2.2 equals 31.2 psig but that would be only for the rears and a little on the high side I would think. I always start with 5 psi differential front to rear and adjust according to the actual tire from driving feel. I have some Nankang tires that work ok on the front at about 35 to 40 psi while the Kumho's on the rear are at 30psi.
The Nankang tires felt like Jello on the rear even at 45 psi.
If I had known I would live this long I would have pushed the envelope a little harder.
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Albert Tiedemann
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Re: Interesting? Footnote about Michelin XAS Tires

#9 Post by Albert Tiedemann »

pascal giai wrote:Michelin XAS are 180HR15
Michelin XVS are 185HR15 or 185VR15

I use 165HR15 on all my 356s with 4.5" rims. They need 2.2kg pressure to work well...
165 mm width is near the limit for 4.5 inch rims. Additional tire width on 4.5 inch rims will cause pinching and unwanted static curvature of the tread pattern. I do not believe that a 180 mm tire would be a recommended width for 4.5 inch rims. I had 155 mm XAS tires on my 56 Speedster with Fuchs 4.5 inch x 15 inch rims. These "classic geometry old tires" are also .80 aspect ratio. Use of tires wider than 165mm [especially 80 series tires ]compromises the space afforded for emergency tire carriage in A and earlier cars and can cause interference with the hood closure when these tires are inflated to normal driving pressures. Also the battery location and cardboard cover is especially vulnerable to damage getting the tire in and out. When a 6V group I battery is installed [for more capacity or lower cost or both] the fit of the cover is compromised and this exacerbates the removal and refit of the emergency tire into the allotted space.
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Paul Ahnell
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Re: Interesting? Footnote about Michelin XAS Tires

#10 Post by Paul Ahnell »

for High Speed, what's wrong with using the driver's manual recommendation for 165-15 "braced" (radial) tires i.e. 25.5 psi Front. 28.5 psi Rear. I use it for my Vredesteins and works pretty well.
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