wheel softness

[Steve Marinello]

There are many different casting processes for wheels, as well as
metallurgy, that impart their strength.  OZ (years ago) made the point that
their cast wheels were made using a modified gravity/low pressure feed to
ensure strength and uniformity.  Their wheels were said to have tested out
much stronger than high pressure cast wheels of similar metallurgy and , in
fact, approached forged strengths according to something I read back then in
the '70's.  Some high pressure methods may, in fact, allow for micro-bubbles
in the matrix which reduce strength.  Also, there are/were the Campagnolo
"Electron" allow wheels out there at that time which were also supposed to
be exceedingly strong.  Had them as original equipment on my '78 Alfetta.
They took everything that was thrown at them, including pot holes and
goofing off "rally driving" down some "roads" through the woods in Alabama
when I lived there.  I remember a picture of someone with a blow torch
heating up an Electron wheel while someone else was beating it with a small
sledge hammer.  No damage.

Steve

----- Original Message -----
From: "Chris Covington" <malth at umich.edu>
To: <quattro at audifans.com>
Sent: Wednesday, November 29, 2000 9:33 AM
Subject: wheel softness


> I think a better way to correlate a cause/effect relationship between
> wheels and softness is to determine whether or not the wheel is forged,
> regardless of brand.  Forged wheels will be much harder: less likely to
> bend or get out of round, and cast will be softer and more likely.  I
> think the majority of BBS wheels are forged (the 91 200q20v stock BBS
> rims) and my 3 piece BBS RF rims are examples.  But so are other wheels,
> like some Speedlines such as on the S4 before the Avus-styled cast
> S6 rims came about.
>
> So it's Cast vs. Forged.  I don't see how the "brand" matters
> unless a certain brand uses exclusively forged rims (HRE?).
>
> '91 2cq
>