Covering 19,000 miles in a 420bhp supersaloon on one set of tyres is pretty much unheard of

The flapping noise from the rear wheelarch could mean only one thing: tyre delamination stops play. Stupidly, it never even crossed my mind that venturing onto the West Circuit at the Bedford Autodrome on a set of tyres that had already covered 18,880 miles could result in disintegrated tread.

All I wanted to do was give the remarkably long-lived Bridgestone Potenzas a suitably smoky send-off, but after a handful of corners they’d pebble-dashed the track with rubber marbles. And then came the end. It was remarkably undramatic: no extra slew sideways, no almighty bang, just the flailing strips of rubber, although they did manage to partially detach the nearside-rear wheelarch spat by bludgeoning a self-tapper to death.

Having not foreseen this situation, I’d neglected to organise a mobile tyre-fitter, so I removed the loose rubber (it pulls off quite easily when hot ‘n’ sticky) and set off for Tyres Northampton, pitting at the office to collect the new (and about £30 a corner more expensive) Michelin Pilot Sports I’d thankfully already ordered.

There was a fair amount of sucking and blowing through pursed lips when the fitters saw the state of the rear Bridgestones, but they also commented that covering almost 19,000 miles in a 420bhp supersaloon on one set of tyres is pretty much unheard of. Seems the IS-F is very gentle on its tyres. Or I drive like a big Jessie.

Having had the scarring on one wheel pointed out to me – a leftover from the snow when the Lexus slid into a kerb as I came to a halt  – I was sent on my way. I took the long way home that evening, curious to see what difference switching to the IS-F’s other OE tyre would make. However, the trouble was that I was comparing a heavily worn set of Bridgestone Potenza RE050As with four spanking new Michelin Pilot Sports, which threw a spanner in the works – the new tyre is bound to be quieter and more comfortable simply due to the extra tread depth.

But there’s more to it than that. The new Michelins undoubtedly have squidgier sidewalls when run at the same pressures, which makes for a softer ride that sends fewer shocks through the suspension (a good thing), but it also robs them of the inch-perfect cornering precision the Bridgestones were so good at.

The outright grip advantage also seems to lie with the Japanese rubber, though I must confess that I think most modern cars have way too much grip anyway, and I rather like the fact that I can now feel the IS-F’s electronic diff working more actively, the car’s tail that bit more mobile and responsive to the throttle.

So while the Potenzas are well-matched to the IS-F’s hardcore character, for commuting and the odd bit of hooliganism, the Pilots suit me and the Lexus just fine.