Hold the curry, we'll be taking the Shogun

CARNIVAL has broken out again. The crowd barriers are piled high at street corners along Ladbroke Grove in west London. Tonight, rhythmic drumming will throb all down the Portobello - the sound of hammers bashing boarding into place over the glass fronts of shop and cafe.

The excitement of Notting Hill derives from this tribal atmosphere. The trouble is, the tribes differ over the attractions of Carnival. Richest among them are the Shogun-Discovery peoples, who live in the stuccoed canyons of its western crescents. Two days of blasting, throbbing noise and high whistles is too much. They are bereft of parking spaces for their 4x4s. The aroma of goat curry assaults them even on their Haddonstone patios.

They flee, resentfully, to their summer pastures in Oxfordshire and Dorset, with little bits of cheese and deli-sausage wrapped in cling film in a cool box in the back. On their way down the M40 one of them will say: 'Are you sure you remembered to switch the alarm on, darling?'

There is a more tolerant ethnic minority in Notting Hill which does not leave town. Its members are the object of discrimination and abuse: people imitate their accents in restaurants. These are the Truffles, the little twenty- something Trust Funders, whose snouts have rummaged from their earliest years in an ancestral trough. Subsidised lives have left them short of stimulation. They like the raffish edge to the Hill, the hairy old men doing deals for strange substances outside the bookies, and the odd patch of vomit in the gutter between 192 and the Osteria Basilico.

So, as soon as university, or art school, or the drama classes are through, their trustees buy them a flat in Notting Hill, as close to the All Saints Road as they can find. Their spare bedrooms are let to Rosie and Francis and Alexandra, who hold dinner parties and unsuitable lovers on alternate nights.

Most of them have ambitions in some artistic field, but they lack edge. They make up for that in contacts. Their clothes are second-hand, or expensively designed to look second-hand, for they are deeply sympathetic to the underprivileged, having sub- consciously absorbed at school the fact that only the nouveau riche are not.

These Truffles love the Carnival. Today they are stockpiling booze and lighter substances for a huge party all-day Monday, when they will dance in the streets. As evening falls, two of them will be so high they will climb through the skylight to the roof, dislodging pounds 200-worth of tiling, and pee on the people going home.

But their love of the Carnival will not, alas, last for ever. One year Francis will be mugged of his Rolex in Westbourne Park Road at knifepoint by two 14- year-olds who already know more than he ever will. And Rosie, who never remembers to double lock the front door, let alone fill in an insurance form, will return one Sunday to find her flat door booted in, the fax and sound system gone, the soft top on her Mazda ripped, and the Carnival Crime Desk permanently engaged. When Carnival looms the year after, someone's stepmother will have a house free in Provence.

For little Truffles become Shoguns when they grow up. In 20 years' time the big houses in Notting Hill, north and south, will contain little else. This is the new Chelsea, with high ceilings, bigger gardens and more trees.

And these two tribal communities, the Truffles, these Shoguns, are the most vocal of the minority ethnic groups in Notting Hill. They sit on councils. Or they know people who do. They don't mind Carnival in itself, you understand, oh dear no. They would just like to see the wild, noisy beast that is Carnival taught tamer tricks.

Already a curfew cuts out the sound systems by 9pm. Now all floats must be licensed in advance. They must join the carnival procession at set points. This year Kensington and Chelsea Council is forbidding sound systems to exceed a set noise level, or else the system is forfeit.

The Carnival, that disorganised expression of mayhem and misrule and, at its best, joy, and, at its worst, fury, is - unthinkable] - beginning, like the area, to be forcibly gentrified.

In All Saints Road even the Mangrove Community Association has office furniture as smart as a City headhunter's bureau. Inside, Jeb Johnson can see a nightmare vision of a bureaucratised Carnival in 2000, each home- made pattie personally probed by health officers, mufflers on every steel drum, sponsored napkins with the goat curry.

'I know it's inconvenient,' he says. 'But it's only two days out of the year. The whole thing about multiculturalism is sharing. Love me, love my dog, love my cat, love my Carnival.'

Mr Johnson shrugs. But the Discoveries outside love neither cat nor Carnival. They just carry on crawling, right out the Hill.

William Donaldson is in Ibiza making a programme for Radio 4, and will return next week.