MOTORING / Me & My Motor: Murray in a hurry gets it together: Matthew Gwyther joins a top motor racing commentator in his new BMW 325i Coupe

YOU DO not get to be a national institution as a sports commentator without having your catchphrase. Dan Maskell made it with 'Oooh, I say - dream volleh'; Harry Carpenter's is 'Well, Frank, how does it look from down there on the canvas?' Murray Walker's is more of an apology: 'What am I saying?' This would, of course, be delivered in what has been described as Walker's highly individual 'trousers on fire' commentary style.

We are out in the New Forest in his smart new BMW 325i Coupe. Although it's capable of a top speed of 140mph, we are beetling along at 40mph as this is a speed-restricted zone to avoid wildlife fatalities. (With hundreds of hectares of heath and woodland to choose from, the horses for some odd reason choose to loiter in the middle of the road.) Murray himself opened the scheme, so it would be a disaster if he were caught exceeding the speed limit.

With slight reluctance, he is recalling one of his most oft-requested gaffes - the one that always gets shown on what the Americans call 'Blooper' shows. It was at the Lydden rally- cross circuit in the 1960s and conditions were extremely muddy; Murray was explaining why the Mini in shot had a hole cut into its windscreen - so that the driver could see where he was going. Before he had finished his sentence, the Mini veered off the track, up a bank and crashed through a hoarding.

Murray Walker has been a BMW man for years. 'I'm unashamedly prepared to admit I'm interested in image, and the BMW has a fabulous image. It all fits together for me.' His father, Graham, was a famous racing motorcyclist in the Twenties and Thirties. 'He was offered a works ride by BMW in 1938,' says Murray, 'but it meant going to live in Germany and he was extremely patriotic. He could see a war coming - and how right he was.'

Murray rode bikes for 45 years, finishing up with a pair of BMWs - an R90 and an R100S. In 1983 he gave up bikes, without having ever hurt himself but feeling they were becoming 'a bit of a hassle'. He is now in his 70th year, and his car insurance for a pounds 23,000 vehicle is less than pounds 500 a year. He drives carefully to maintain his no claims bonus, and the interior of his 325 is immaculate - a 'No Smoking' sticker by the gearstick, neatly arranged road maps in the driver's door compartment. The seats are done in cream leather. 'The BMW 3-Series is ideal for me,' he says. 'I don't need a big car - we never had any children - and these ones are bloody marvellous in terms of quality. Mind you, I can put my hand on my heart and say I've never had a bad motor car, a real lemon. Maybe I'm not very demanding.'

The most remarkable thing about Murray is that, although he has been commentating since 1949, for the bulk of that time it was a part-time hobby. His main career was as an adman with the agency D'Arcy McManus and Masius. He'd finish in London on a Friday night, jump on his bike and spend the weekend with his trousers on fire at Silverstone or Brands Hatch.

His enthusiasm for the sport remains entirely genuine. 'I'm fantastically lucky,' he says. 'I love doing what I get paid for, and I'll carry on until lack of physical or mental ability to keep up stops me. I suppose I'm a frustrated racer at heart, and at first I had delusions of replicating my father's success. But either I wasn't good enough, or it didn't matter enough.'

Motor racing is thought by television professionals to be the trickiest sport to commentate on (he's doing the Hungarian Grand Prix this afternoon on BBC2). It is noisy, you cannot see most of what is happening and you are reliant on some dodgy foreign TV producers.

'In the commentary box I am faced with one monitor. I see the same picture as you and nothing else. Yes, I can, and sometimes do, look away from the monitor to try and work out what is going on. Inevitably, that is the moment when you see the leader leave the track, hit the Armco, burst into flames, get out of the car, punch a marshal and meanwhile I'm saying 'Here's something interesting, Martin Brundle has moved up into seventh position.' And you all say: 'Why don't they get someone who knows what he's talking about?' '

The adman in him admires BMW's marketing efforts in this country. It all came together for BMW in the 1980s, and the Munich-based manuacturer became the most potent symbol of that decade. Murray had been driving a lot of Vauxhalls because his agency held the account: 'They were not the most desirable car in the world, to put it mildly. They had a terrible rust-bucket image but we helped in an absolutely fabulous job of turning it around.'

As an agency director, Murray got to drive the top-of-the-range model, the Viscount. 'I used to call it the Squidgemobile. It had a 3.3- litre Bedford truck engine, suitably modified automatic gearbox, and electric windows.'

Like Ernie Wise, Walker is now going solo after the other half of his double act died. He and James Hunt were a pretty unlikely pairing, but they became one of the great television partnerships of the age: James Hunt - public school, laconic and drawling; Murray Walker - his trousers going up in flames, working himself up into a right old lather.

But they did not hit it off immediately. 'It would be hard to imagine two people more different in terms of personality, attitude and beliefs,' Murray says. 'That's probably why we ended up getting on so well. But we didn't always. I was mildly concerned about having an ex-racing driver in the commentary box. James and I knocked the rough edges off each other.' Walker had to suppress a tearful gulp when he filmed the BBC's tribute to his old colleague.

Despite having been close to Formula One for so long, he has only once got to drive one of the cars. McLaren invited him to Silverstone for a test spin. He was terrified - he knew everyone was watching, waiting for him to make a gaffe. 'I didn't want to stall it, or stuff it into the Armco. But actually Formula One cars are very easy to drive - the brakes, the steering, the gears are near-enough normal. The problem is finding out how fast you can go.'

His father's racing genes saw him through, however. Murray ended up doing 10 laps, and such was his enthusiasm that he missed the sign hung out to bring him back into the pits.

(Photograph omitted)