Date:         Wed, 21 Oct 1998 10:53:15 -0700
Reply-To:     Malcolm Holser <mholser@ADOBE.COM>
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         Malcolm Holser <mholser@ADOBE.COM>
Subject:      Re: Yokohama tires: math lesson
Comments: To: Budd Premack <bpremack@WAVETECH.NET>, vanagon@VANAGON.COM
In-Reply-To:  <199810210504.AAA24620@riptide.wavetech.net>
Content-Type: text/plain; charset="us-ascii"

Well, I'll let you guys debate the math (and what is meant by "10% larger")
but I would like to point out that we usually don't run 195/60 tires -- rather
we run larger tires like 195/75.  The "195" or "205" refers to the width of
the
tire in millimeters -- about 8" for these guys.  The 60, 65, 70, 75 (or 40 for
you Viper-drivers) refers to the percentage of the width the sidewall has.
You can add up these to sort of get the diameter -- the wheelsize +
(2*width*ratio/100)
once you convert all the terms to similar measures.

In any event, a 205/70 tire is not much different in diameter than the 195/75.
Both tires are suitable, but if you go to a 195 width the pressure needs to be
up to a 50lb rating, and you must get a reinforced or LT tire.  The wider
tires
need lower pressure (since they have a larger width and hence larger contact
surface to spread the weight out over).  The contact area goes up basically
by the
square of the width (kinda, sorta), so the pressure should be reduced by a
similar
ratio.

There are limits to how wide a tire you can mount on a Vanagon rim.  You
can use
wider rims, 15" or 16" and get lower profile tires to get wider tires
without a
serious change in tire diameter.  For all wider tires, though, you will
need to
reduce the tire pressure.  Tire dealers will have books on this, and
Michelin, at
least, lists some wider passenger tires at lower pressures as suitable for
Vanagons.

I run these on my GL.  Michelin offers their full (80,000miles?) warrantee,
so they
must feel fairly confident -- at least the place that installed them said so.

That said, on my other Vanagons, I run truck tires.  The Westies are
overloaded
sitting empty, and I have overloaded both my transporters on a routine basis.
On my doublecab, I am running 225/75-15LT tires.  I'd run the same on the
Kombi
but I need to find some wheels eventually.

Do they even make 195/60-14 tires?  They must be cute.

Malcolm H.