Tread wear is governed by the compound used in the
Soft compound = grippy tyres but high treadwear
Hard compound = low performance tyres with low wear
You can approximate the normal use mileage you can get
out of a tyre by looking at the treadwear rating.
Typically Jaguar XJ40’s have tyres fitted as standars
with 180 to 200 treadwear rating. This means that they
SHOULD last 36000 miles (multiply treadwear rating by
200) in normal driving conditiuns.
A harder tyre (like the Pirelli Super Touring) will
have a treadwear rating of 320, which gives a life of
I have 205/70 15 Pirelli Super Tourings fitted to
Bertie, and while thay may last a long time, the car
handles like a boat in stormy seas… especially when
the rear tyre pressures drop below 30 psi ! (should be
36 for best handling).
The new kid on the block is the ‘Eco’ tyre or ‘Energy’
tyre that contains a large amount of silicon.
These tyres can give long treadlife (340 rating) while
giving good levels of grip in both wet and dry
conditions, thanks to the way the silicon compound
They also offer significant (up to 5%) reduction in
fuel consumption… but only at low vehicle speeds
where aerodynamic losses are low and rolling
resistance is the major factor. This is something that
the manufacturers advertising campaigns will not tell
Due to their distinct advantages these silicon
compound tyres are becoming the industry ‘Norm’ to fit
to European saloons to reduce emissions over the Euro
drive cycle and to reduce fuel consumption as fuel
prices reach astronomical levels.
They’re no ‘Racing’ tyre, but they are certainly the
best overall compromise of wear, performance, safety
and rolling resistance.
Steve & the LPG '93____________________________________________________________
Do You Yahoo!?
Get your free @yahoo.co.uk address at http://mail.yahoo.co.uk
or your free @yahoo.ie address at http://mail.yahoo.ie