Tyres, aspect ratio, and speedo accuracy

["Leslie J. Singh" <Les.Singh@domain.elided>]

Hi All

The digest is getting a bit dull these days so let's have some controversy,
andy by the way where is Olga now? !!!

It intrigues me that some people who drive Alfas and ostensibly bought one
because it is a performance car, would opt for a tyre size simply because
it maintains speedo accuracy - whatever that may mean. Checked your speedo
lately? Does anyone have a problem working out 10% of a value?

I have a range of wheels and tyres that I use on the Green GTV, everything
from 205-60 X 13 on 6.5 inch 3-piece wheels, through 195-65 x 14, to 195-60
x 15. Every one of these has advantages and disadvantages. The 15 inch, for
example is way too heavy for the suspension as it is set up, and this is
especially noticeable on rebound. The 195-65 x 14 tyre is a compromise tyre
that gives adequate ground clearance and almost acceptable handling for
town use but just does not match up to the 195-60 x 14 for great handling,
enhanced acceleration, and that indefinable "feel". Compare prices - the
60% aspect ratio tyre is always more expensive because of its superior
construction than the equivalent 65% tyre. 

Before I get shot down in flames, I'm comparing eggs with eggs: all of
these comparisons are based on the Pirelli P6. The 205-60 x 13 however,  is
a special road-legal race tyre so it doesn't enter into the equation -
sticky high-wear compound with just enough grooving to make it road legal.
It makes the steering very heavy at low speeds partly because of the low
pressures 24/22. 

I concur with Mark Battley and others - the 195-60 wins hands down when I'm
choosing a road tyre. My pet hate at the moment - older Alfas made to look
like oversized baby-buggies because of superlarge (17" etc) stupid-looking
wheels - and their owners still can't corner fast enough not to hold up
traffic........ flame away!!!! :-)

Les in Wellington , New Zealand not a million miles from where Bill Clinton
is right now...  

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