Dave:
The original MGA tire had a very narrow footprint and would not generate
very high sideways loads before sliding. Radials have a much wider
footprint and subsequent high loading can cause the 48 spoke wheels to
flex too much causing spoke breakage and warpage.
The wire wheel is much more forgiving than a disc wheel since in this
case there are 48 spokes that flex under load, rather than one stamped
steel disc. Given enough flexing though, anything will fatigue and
fracture. If a spoke fails, there are 47 left to keep you motoring, if
the center rips out of a disc wheel.... I guess you have 3 wheels left
on the road, you just have to lean a bit.
The safety issue is more due to lack of maintenance and knowledge,
rather than a worry that the wheel could instantly fail under load. A
wire wheel will give lots of warning before becoming a safety issue, IF
you know what to look and listen for. The main thing is that the 48
spoke wheels will tend to need constant work to keep true and there will
be a tendency for the spokes and nipples to fail. The 60 spoke wheels
are much stronger and more suitable for the increased loading that can
be encountered with radial tires.
I hope this answers the question.
Kelvin.
-----Original Message-----
From: owner-mgs@autox.team.net [mailto:owner-mgs@autox.team.net] On
Behalf Of David Breneman (DHL US)
Sent: Tuesday, May 11, 2004 12:28 PM
To: Mgs
Subject: RE: Spoke wheels vs. disk:
Which leaves me to wonder...
Then why do so many people believe you should only use 60-spoke racing
wheels on MGAs with radial tires? I've always been of the opinion that
for street use, the 48-spoke originals are fine, but some folks will
swear that you're taking your life in your hands using them even in
driving to
the corner market. :-) So in the final analysis, flexibility is a
good
thing, although once the spokes start to break, they get a little *too*
flexible! :-)
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