Contributing editor Steve Banner has been talking to Peter Robb and Gwyn Fennell, brand manager and technical services manager respectively, for the Continental Tyre Group in the UK.
As a major tyre manufacturer, is Continental finding that the recession is prompting light commercial owners to put off replacing tyres that desperately need changing?
PR No. Our best-guess estimate is that around 2.5m replacement van tyres are sold annually in Britain and sales have grown by around three per cent year-to-date. The market is quite buoyant and will probably continue to be so for the next few months. However, we may not have seen the full impact of the economic downturn on the demand for tyres. For example, we may find over the next year that van owners who have been in the habit of changing their tyres when the tread depth reaches 2mm will instead wait until it reaches 1.6mm across three-quarters of the width of the tread; the legal limit. If they go even further and start running on tyres that have gone beyond the legal limit then that’s going to be a serious cause for concern because they will have become more worried about their wallets than about safety. Don’t forget by the way that a 3mm tyre tread depth gives you a braking distance that is two bus lengths shorter than what’s on offer from a 1.6mm depth.
Are there any other factors that could reduce the demand for tyres?
PR Another one is the fact that light commercials don’t cover so many miles during a downturn because there’s less business around. Looking ahead, the replacement market is likely to feel the pinch in 2010/2011 because fewer new vans are being sold now and as a consequence fewer vans will require their tyres changing in two or three years time. In this context it’s worth noting that one in three light commercials are fitted with Continental tyres on the production line.
If you look after your tyres then they’ll last longer and you’ll be a lot safer into the bargain. But what are the tell-tale signs of danger? Should I be worried if, for example, I spot a bulge in a tyre’s sidewall?
GF If it’s soft in the centre then that indicates that there’s a separation in the tyre’s structure — it’s coming apart in other words — and that could lead to the tyre failing.
What happens if I don’t check my tyre pressures regularly?
GF If your inflation pressure is incorrect then you’ll get a less-comfortable ride and your fuel consumption will get worse too.
PR If your tyres are 20 per cent under-inflated then your fuel consumption will go up by around three per cent; quite a significant amount of money over the lifetime of a vehicle.
What about tyre life?
PR Twenty per cent under-inflation can cut it by as much as 20 per cent. Remember that the stress on van tyres is enormous and that they have to work a lot harder if the inflation pressure is wrong. You should really check your tyre pressures at least once a week and carry out a visual inspection of your tyres at the same time.
GF Don’t forget that van tyres regularly get driven up over kerbs or scuffed against them and damage can be done as a consequence. That’s despite the fact that light commercial tyres are built to resist kerbing, with kerbing bands and reinforced rubber. In fact if the tyres have felt any impact during a journey then it is good practice to give them a check-over as soon as possible.
What if I over-inflate my tyres?
GF You’ll get increased wear over the centre area of the tread and again that will reduce the tyre’s life.
PR Twenty per cent over-inflation means that the tyre’s life is cut by 20 per cent.
GF Unfortunately people don’t check their tyres as often as they should. That’s despite the fact that from the viewpoint of both safety and the tyre’s longevity it’s vitally important that maintenance is improved rather than relaxed. If you want to get the most out of what you’ve got then you’ve got to maintain it properly. When we talk about maintenance incidentally we’re not just talking about tyres, but about other aspects of the vehicle such as the tracking, not to mention adhering to regular service intervals. Such things may be perceived as a cost but could save you money in the long run.
Surely under- or over-inflation of a van’s tyres will affect its handling?
GF It certainly will. If a tyre is correctly inflated then when the limit of its adhesion is reached it will break away in a controlled and gradual manner. If it is not, then the break-away is likely to occur earlier and in a much more severe fashion. That could result in the driver losing control of the vehicle. Under- or over-inflation is likely to have a negative impact on braking distances too.
PR Remember that a lot of dealers offer free tyre pressure checks and will check the general condition of your tyres as well.
Advertisements regularly appear all over the country promoting second-hand/part-worn tyres. Should they be avoided?
GF You cannot be certain about a used tyre’s history and that means there are potential risks. A while back we purchased and examined a number of second-hand tyres and found that several of them had penetration damage that had been incorrectly repaired. One of the tyres we examined was 12 years old. If you are thinking about buying a used tyre, then if the tread depth is legal you should ask yourself why it was removed from the vehicle it was on previously and why the vendor is attempting to sell it.
How comprehensive is your light commercial tyre range?
PR We cover the majority of applications. Our latest model is the Vanco 2, which came out in 2007. It’s designed for vehicles grossing at from 1.8 to 3.5 tonnes. In developing it we moved away a little from traditional van tyre performance requirements. It’s always been the case that there has been a strong emphasis on mileage, durability and load carrying capacity. Vanco 2 performs well in all of those areas — potential mileage is up by 20 per cent — but it has also been developed in response to the improvements in van performance in recent years. As a consequence more stress has been placed on handling and behaviour in wet weather. It has more grooves to protect against aquaplaning than its predecessor, for example, and the way in which it is designed should result in shorter braking distances. For smaller vans we’ve got the Vanco Contact 2.
What do you think the key trends will be over the next few years in terms of van tyre sizes?
PR I think there will be a greater emphasis on 16in sizes so far as panel van tyres are concerned — 16in rim sizes now represent half of the market with six 16in sizes in the top ten — with several variants within that size. Go smaller and you’ll find the brake discs won’t fit the wheel. Go bigger, and opt for low profiles, and you can face ride comfort issues.
A number of manufacturers are offering higher-performance versions of their mainstream models. How are you responding to that demand?
PR We’re increasingly offering 4x4 tyres for that sort of application and in this instance I mean tyres that are designed for 80 per cent on-road/20 per cent off-road use. They will fit the rim diameters manufacturers want to use and their construction gives them the necessary performance, mileage, durability and load carrying capacity.
Might that be one way of avoiding the sort of difficulties that arose with the 235/45 Z R18 low-profile Continental Sport Contact 2 fitted to the 18in alloy front wheels of Ford’s fancily-styled front-wheel drive Transit SportVan? In 2008 a number of owners complained to What Van? that they were not getting the mileage they expected out of tyres that seemed better-suited to passenger car applications.
PR To a certain extent, but 4x4 tyres still have a reasonably-high profile. They’re not low-profile tyres. As for SportVan, the main requirements for the vehicle were to handle and stop well. That’s why we had to put a passenger car tyre on it and we certainly haven’t received any complaints about the tyre’s performance. From that viewpoint it ticked all the boxes. It matched Ford’s specifications and is in fact going to be used on Transit Connect SportVan. So far as its mileage is concerned we’re still looking into it to see if there’s anything we can do, but no definite decision has been made over the action that will be taken.
Do you think we will see a move away from vans carrying spare tyres and sealant kits being provided instead in order to save cost and weight?
PR We offer something called the Conti Comfort Kit but the compressor isn’t powerful enough to allow it to be used for most van applications. We’re looking at providing a version suitable for vans but it’s unlikely that we’ll see it before 2010. There’s a lot of interest in this approach though and it’s a definite trend for the future.
Do you expect on-board systems that warn the driver if a tyre is starting to lose pressure to become more common?
PR At present it’s up to the van manufacturers as to whether they want to offer them or not, but I think they will become mandatory in Europe within the next few years.
GF However, they should not be treated as an alternative to regularly checking your tyres.
You’ve argued that van operators in the UK should consider switching to cold weather tyres in the winter months. Why on earth should they want to given that in most parts of the country we don’t experience huge falls in temperature?
GF A cold weather tyre typically starts to out-perform a summer tyre at temperatures below 7°C; temperatures that are found throughout the UK during six months of the year.
PR Use a cold weather tyre at below 7°C and you’ll get 20 per cent more mileage out of it than you will out of a standard tyre.
The price of a barrel of oil has plummeted in recent months and oil is a major constituent of tyres. Are tyre prices set to decline as a consequence, particularly given the steep fall in demand from vehicle assemblers thanks to the recession?
PR That’s only part of the story. We have to keep making major investments in technology and that’s one reason why there is no indication that tyre prices will fall heavily. Technology does not come cheap.