Date: Fri, 14 Aug 1998 00:10:28 EDT
Reply-To: KBrennan@AOL.COM
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: Kim Brennan <KBrennan@AOL.COM>
Subject: Wheels (reprise)
Content-type: text/plain; charset=US-ASCII
Okay, I got several responses about my wheels question. Unfortunately, it is
obvious to me that either 1) people didn't read what I wrote, or 2) don't
understand the question.
The question was, what is the maximum size WIDTH, on a WHEEL on a Syncro
Vanagon.
I got several responses from folks indicating what they thought was the
maximum size TIRE.
TIRE does not equal WHEEL.
I can use a 205 mm wide tire on a 5 inch wide rim, a 5.5" wide rim, a 6" wide
rim, a 6.5" wide rim, a 7" wide rim, a 7.5" wide rim, and maybe even an 8"
wide rim.
Something else that I deduce from the responses is a lack of understanding
regarding offset. As you change wheel widths, offset is NOT a constant.
European Car magazine had a very good article on offset a year or two ago, and
maybe if I'm really into educating the list, I'll paraphrase some of the
details.
The basic idea though, as a few people no doubt already know, is that if you
have the wrong offset such that your wheel (and tire) are too far towards the
middle of the car, you won't have proper clearence for some of the other
mechanicals. Too far towards the outside, and you put extra (undesired) stress
on the axles.
As you go with wider wheels (NOT tires), you need to adjust the offset to try
to keep the center of mass of the wheel in the correct place for the axles.
The issue, I'm inquiring about is, if one has the correct offset, how wide can
the wheel be before it interferes with the mechanicals.
Now, BEFORE folks respond.. let me show the range of answers:
One person claimed that his 6" audi wheels barely fit.
Yet, another said he was using 7" wheels with plenty of room.
Another has 7.5" wide wheels.
I stand corrected on the "factory" allows (I thought they were 15", but it is
reported to me that they are in fact 14" wheels 5.5" wide. Eurospec's wheels
as advertised are 15" x 6.5" wide.
I conclude from this (before looking at the impirical evidence that the person
with the Audi wheels has the wrong offset for use on a Vanagon.
Additional information. There are a lot of folks that make the assumption that
larger wheels will automatically mean more weight for the wheel/tire combo.
This is not a valid assumption. It may actually happen in some cases. However,
it is not a guaranteed situation. Aluminum alloys can be lighter than steel
wheels. Even in a larger size. And I won't even talk about magnesium wheels
(not likely to be found on a Vanagon anyway :) ! Even if the allow wheel (in a
larger diameter) is equal in weight a steel wheel, the fact that there is less
tire weight for a given rolling diameter will keep the overall wheel/tire
weight less on a larger allow wheel than a smaller steel wheel.