MOTOR CARAVAN TYRES TECHNICAL Tyre maintenance is an important aspect of motor caravan safety Tread carefully John Wickersham explains how to maintain your motor caravan’s tyres and what to consider when looking for replacements T HE CLUB’S technical leaflet, Caravan Tyres & Wheels, is an invaluable document that includes guidance on tyre care, life, sealants, wear and so on. Although this is principally concerned with caravan tyres, its appendices include information that’s also applicable to motor caravans. This report takes the topic further. GENERAL POINTS Continental’s VancoCamper tyre is an example of a purpose-designed motor caravan product Manufactured in the 23rd week of 2004, this tyre should now be replaced, even if its treads look good Although a few small motor caravans run on car tyres, most are based on light commercial vehicles that are fitted with commercial tyres. In some cases, coachbuilt models have purpose-made motor caravan tyres. For example, Michelin’s ‘XC Camping’ and ‘Agilis Camping’ are intentionally designed to carry heavy loads. Thanks to their reinforced construction, these products can also operate with high pressures (up to 80psi). A ‘CP’ suffix after the tyre size denotes a purpose-made motor caravan tyre. NEW VEHICLES If you’re planning to buy a new motor caravan, be aware that some are sold >> Sealant kits for dealing with unexpected punctures cannot be used when a tyre has damaged side walls August 2011 The Caravan Club Magazine 101 TECHNICAL MOTOR CARAVAN TYRES After long periods in storage, it’s not unusual to find cracks developing in a tyre’s sidewalls Get a tyre service fitter to check your tyre pressures if you don’t want to do this yourself without a spare wheel and don’t have a wheel carrier either. To deal with roadside punctures, some manufactures provide an emergency tyre sealant kit instead. However, since these can’t repair a tyre whose sidewalls are damaged, an easily accessed spare wheel is what many owners prefer. PRE-OWNED MODELS If you’re buying a second-hand motor caravan, always inspect the tyres. The Club recommends that tyres are replaced after five years – and that they should never be used when more than seven years old. However, assessing age can be difficult and marking codes differ. Usually there’s a four-figure marking giving the week number and year of manufacture. Please note that life expectancy is reduced by rapid acceleration, forceful driving, overloading, incorrect inflation and kerb damage. Dial gauges are usually accurate – look for products with a wide range You must also avoid under-inflation. If a tyre’s pressure is 20% lower than it should be for the load carried, that also reduces its life by around 26%. because large manufacturers such as Fiat sometimes place huge orders, prompted by seasonal demands. This leaves few tyres available for retailers. TAKING PRESSURE READINGS RETRIEVING/CHECKING A SPARE Pressure tests must be done when tyres are cold (some specialists define ‘cold’ as being no higher than 17˚C). The Caravan Club also reports that when comparing types of gauge, dial gauges are “most likely to be really accurate”, especially if marked with a relevant standard, such as EN 12645. There’s also the pressure range itself to consider; normally the most accurate readings fall at a scale’s mid-point. For motor caravan tyres, a dial range from 1psi to 150psi is fine. When looking to buy a motor caravan, it is wise to check if there’s a spare wheel and to establish if it’s simple to retrieve. Coachbuilt models with rear garages often have easily accessible spares. A few models have wheels mounted on the rear wall – or right on the front in the case of some VW campers. Wheels stored in under-floor cages are usually the hardest to withdraw. FINDING OUT THE REQUIRED PRESSURES Both touring and motor caravans are often unused for long spells and a lack of movement places tyre sidewalls under stress. This eventually leads to damage. Periodic MOT and owner inspections may also reveal trapped objects that have penetrated the casing. Motor caravan manufacturers should specify the correct pressure settings in their owners’ manuals and these are sometimes displayed on labels on the vehicles themselves. Unfortunately, some labels aren’t easy to decipher. Moreover, any markings on tyres specifying maximum loads and pressures should be ignored since these are for North America and are not applicable in the UK. CORRECT LOADING AND INFLATION BUYING REPLACEMENTS A warning issued by the Michelin technical staff suggests that if you overload a tyre 20% more than a recommended limit, its life will be reduced by around 26%. When planning to buy motor caravanspecific tyres, be aware of a potential problem. On occasions there are supply delays of six to eight weeks. Delays arise SIDEWALL WEAR Sometimes tyre specialists have to wait a long time for a delivery of motor caravan tyres 102 The Caravan Club Magazine Vehicle labels can be confusing and some motor caravan manufacturers remove them The ease of retrieving a spare wheel from a motor caravan varies a great deal WHEEL SAFETY BANDS If there’s an unexpected tyre failure when you’re driving, a deflated casing can easily fall into the well of a wheel. This causes its beading to pull away from the rim whereupon wheel metal makes direct contact with the road. This can be prevented if safety bands (such as those made by Tyron) are fitted in the well. If a tyre suddenly deflates, the band keeps it in place so rubber remains in contact with the road, thereby helping stability. n FURTHER INFORMATION n The Caravan Club’s Caravan Tyres and Wheels technical leaflet can be found at caravanclub.co.uk/practical-advice n Tyron Safety Bands – call 0845 400 0600 or see tyron.com Safety bands fitted into the wells of wheels aid stability if a puncture occurs