For some time now, a video (www.facebook.com/reel/5904404246262444/) has been all the rage on social media, in which a motorhome, while negotiating a downhill hairpin bend, suddenly loses grip on a snow-clad road and its driver deftly counter steers to get it back on the 'straight and narrow'. A situation that no one, especially RV drivers, would ever want to experience, even knowing that they can rely on their own driving skills and the quality and condition of the tyres fitted to their vehicles. Drifting and counter-steering should not be part of a motorhome driver's technical daily routine (and in fact the situation shown in the video is quite exceptional) who, on the other hand, should always be able to rely on tyres in perfect order that are up to the task. "The fact that these vehicles are driven only occasionally and quite often for short periods (mainly on weekends or public holidays, in addition to summer holidays) could lead to a general underestimating the importance of the tyres," explains Alessandro Cortellessa of Caravan & Camper Granturismo magazine, who happens to be quite familiar with this world. These vehicles generally cover only about 5,000 to 10,000 kilometres a year, meaning that the tyres wear very little on the tread, but still deteriorate over time, both because they are called upon to support a vehicle weighing 3.5 tonnes (and often much more, beyond the certified limits) and because they are frequently left standing for a long time outdoors in storage, almost always in the scorching sun or intense cold, which accelerates the deterioration process".
And since the living area of an RV (the 'panelled' section of a motorhome, not for those called 'campervans', which are in fact modified vans) is structurally lighter, made of wood, polyester resin or fibreglass, the economic consequences of a rear tyre blowout can be very serious, with damages even to interior furnishings, as well as dangerous and costly damages to the walls or wheel arches, the cost of which could exceed that of a new set of tyres. Unfortunately, it is rather common for RV tyres to have to be changed with a tread that, to the naked eye, looks still half-new, having been driven for few miles, but now potentially dangerous due to their age, made worse by the environmental conditions, the use made of the vehicle, which is in fact always overweight and often parked in the sun.
The RV tyre market, however, represents a niche in the industry and, as such, does not get as much attention from all manufacturers as it would otherwise deserve. Especially in the light of the potential safety consequences and the underestimation of the problem mentioned earlier by users, who are reluctant to replace tyres that are apparently still in perfect condition. Unlike cars, for which there is an enormous variety of tyres, in the case of RVs the sizes (and specific tyres available) are few, partly because as these vehicles are all derived from vans found in the market, customers tend to use products designed for light commercial vehicles, i.e. with the 'C' (Commercial) marking designed to carry a 'light' load (up to 3.5 tonnes), thanks to a structure that guarantees more resistance and stronger shoulders than normal passenger car tyres. RVs, however, have additional standard equipment (kitchen, bathroom, furniture, beds, luggage etc.) compared to the commercial vehicle on which it is built, and above all, unlike their commercial counterparts, RVs travel permanently fully laden, if not overloaded, and is parked and stored in the same condition. Therefore, the tyres are subjected to greater wear and tear than normally expected when fitted to a campervan or even worse a motorhome. The choice of tyres should therefore be made carefully. When purchasing tyres, it is certainly worthwhile to orientate oneself, if possible, towards products that are also reinforced, but above all specific for use on RVs and recognisable externally by the special CP marking. The C and CP codes are not the same thing. If the registration certificate shows the CP marking, this means that only tyres with this code may be fitted.
Many specific needs
One of the toughest tests that such tyres have to face is the response during cornering and emergency manoeuvres, such as the one shown, for example, in the video mentioned at the beginning. In these cases, in fact, when negotiating fast corners or in a sharp turn to avoid an obstacle or a possible collision, in addition to the load shifting on the shoulder of the tyre, there is also a leverage effect that increases as the height - and consequently the centre of gravity - increases (coachbuilts easily exceed three metres), thus placing a much greater load on the tyre, equal to double the normal weight transported. For this reason, tyres intended for RVs are sometimes designed and manufactured specifically for this type of vehicles, and can be even sturdier than those designed for commercial vehicles, even though coming from a similar base, with the addition of reinforcing plies (8, 10 or even 12), in order to minimise one of the most harmful effects afflicting these tyres, flat spots, due to long periods of parking, which is quite the norm for this category of vehicles. Such a tyre penalises the agility of the vehicle, less ply means greater driveability in cornering, but on the other hand, a sturdier structure makes the tyre more “insensitive” to deformation and able to handle edges and kerbs and accidental bumps and avoid the dreaded flat spot when left standing for long periods of time.
Broad and strong shoulders
The difference between tyres designed for passenger cars, light transport and RVs lies in the casing, i.e. the ply structure that is embedded in the rubber, which is much more robust, squared off and high on the sidewalls, as well as having a tread with a larger footprint. In fact, RV tyres (as well as those intended for commercial vehicles) must be able to support heavier loads without suffering from deformation to the shoulders, guarantee resistance to gruelling working conditions and hold a good inflation pressure, so it is also worth considering steel-reinforced valves. Then, of course, they must also stick to the road, provide stability, disperse water efficiently in rainy conditions, offer adequate mileage and tear resistance, and this holds true whether we speak of single or dual tyres, i.e. tyres that can be used individually or in pairs (twins).
Bridgestone Duravis All Season is a four-season tyre is a light transport model designed to reduce the overall costs of small and large fleets, but which can also be used on RVs. It features an "A" label for wet grip as the shoulder grooves provide excellent water drainage, and an innovative sidewall protection bead that protects the tyre from damage caused by impacts against edges and kerbs. An even distribution of the footprint and a compound made with NanoPro-Tech technology enables it to maintain control on wet and snowy roads. Available in 12 different sizes.
Vanco Camper is Continental's proposal for campers. It stands out for its driving stability, guaranteed even when fully loaded, its resistance in all conditions (even on the roughest terrain typical of camping), and its short braking distance in the wet. Fitted as original equipment on Fiat, Ford and Renault commercial vehicles, it is available in four sizes for 15- and 16-inch wheels.
On the market for four years now, the Goodyear Vector 4Seasons Cargo is a four-season tyre designed for light commercial vehicles, but also successfully used on Recreational Vehicles. Its favourable impact on fuel consumption, excellent performance and durability are its main features. Drivers can rely on consistently safe behaviour on any road surface and short braking distances. It is available in 21 sizes for wheels from 14 to 17 inches.
At the beginning of 2020, Michelin’s range was enriched with an all-season RV-specific tyre (CP) expressly designed for those who use their vehicles throughout the year, but also for vehicles that may be parked for a long time. Certified class "A" in wet grip, Michelin CrossClimate Camping is equipped with the M+S marking, making it suitable for use on roads where winter equipment may compulsory, and 3PMSF (3 Peak Mountain Snowflake) certification. The "V"-shaped tread pattern is specially designed for this type of all-season tyre and combines massive tread blocks with an enlarged V-shaped directional channel section to enable driving on dry, wet and snowy surfaces. This technology enhances handling on multiple types of surfaces such as grass, mud, gravel, dirt and snow. CrossClimate Camping comes in 8 different sizes. The Michelin range also includes the Agilis Alpin, a 100% winter tyre with C marking (and therefore suitable for commercial vehicles and RVs that do not require a CP on their registration). Designed by Michelin to offer high levels of acceleration and exceptional control and mobility on snow (3PMSF), the Agilis Alpin can withstand heavy loads and harsh conditions. Braking in winter conditions and excellent mileage are other features highlighted by the manufacturer. Available in 22 sizes.