tyre test - dunlop sport maxx rt
Developing a performance tyre is a subtle exercise in balancing all manner of compromises. Andy Enright takes a look at Dunlop's latest effort, the Sport Maxx RT.
Developing tyres is a black art and some master it better than others. We've all heard the line about how your rubber is the most important component of your car. That you're putting all of the technology of your vehicle to the road through four contact points, each the size of your palm and so on, but to even the more informed consumers amongst us, actually choosing a replacement tyre for your car can be a dizzying experience. Especially if it's for a high performance vehicle.
As few will ever get to try the product they're just about to plough hundreds of pounds into, tyre buyers tend to make the buying decision based on all kinds of claims and usually on the reputation of tyres trusted in the past. Dunlop believes it doesn't have to be this way and in the shape of the Sport Maxx RT claims to have a high performance tyre that's demonstrably superior to its key rivals.
So what exactly do we have here? Well, a tyre designed to appeal to high performance road drivers who might otherwise have chosen something like a Pirelli Pzero, a Goodyear Eagle F1, a Bridgestone Potenza S001, a Michelin PilotSport3 or a Continental ContiSportContact5, tyres you may already be familiar with. This is a tough nut to crack. These aren't full-on track tyres that optimise dry weather grip at the expense of virtually every other criterion. They have to perform well in both wet and dry conditions and still offer the sort of low rolling resistance and noise levels that road drivers demand. In the T£V tests, when fitted to a Golf GTI in the popular 245/45R 17, the Sport Maxx RT outperformed its key competitors by 7 per cent in wet and dry braking tests and by 11 per cent when it came to rolling resistance.
There's some interesting technology going on with the Sport Maxx RT. To reduce braking distances, Dunlop has developed reinforced blocks that ensure an "anti-lift" effect thanks to an increased stiffness. In practice, these grooves connect the V-shaped tread blocks. To provide optimum grip, the Dunlop Sport Maxx RT uses an adaptive compound which compensates for any micro-irregularities in the road surface to ensure a maximum contact area with the ground. In order to improve the steering responsiveness and precision of its tyre, Dunlop Sport Maxx RT has a massive outer shoulder block. This allows the tread pattern to perform efficiently when subjected to high stresses. So you get a big contact patch that's supple where it touches the tarmac yet incredibly rigid in its structure.
Does all this technology work? Exhaustive independent tests by the German T£V standards body seem to suggest that it does. Hence this tyre maker's optimism. "In 2012 we are introducing the Sport Maxx RT to ensure we can continue to claim a leading position in the Ultra High Performance (UHP) tyre market", explains Sanjay Khanna, Managing Director, Dunlop Brand. "We are seeing a solid growth in the UHP market and the Sport Maxx RT will help us deliver on this demand." The Sport Maxx RT introduction comes at a time when drivers and original equipment manufacturers (OEM) are increasingly walking away from 16 inch rims and expanding strongly into 17 and 18 inch rims, two sizes which the Sport Maxx RT will cater to.
Dunlop is looking to build on its motorsport links to help build awareness of the Sport Maxx RT - indeed the RT part stands for Racing Technology - and they also offer a pricier Sport Maxx Race tyre for proper track work but as a compromise tyre that most performance drivers will like, the RT looks promising. Initial tests suggest that it's superb in the sort of mixed wet and dry conditions that often prevail in this country, with its low rolling resistance also working well in terms of fuel economy too. Testers report that it's maybe not quite as lively on turn-in as some rivals and may well be a little noisier, but developing a tyre is an exercise in managing compromises and the RT's payoff comes in the form of excellent high-speed stability.
This tyre replaces the Sport Maxx TT that you might have seen wrapping the rims of the almost universally exalted Renaultsport Megane and looks set to build on its predecessor's success. You wouldn't bet against it.