jhorsf Posted May 12, 2009 Share Posted May 12, 2009 braunston - 2009-05-12 2:05 PM Hi, I have looked at the load ratings on most of the major tyre manufacturers specifications and it seems very difficult to understand/identify the difference between those that make a camping variant and their normal van tyre. Does anyone know the reason for using the camping variant tyres rather than a none camping variant tyre. Thanks camping tyres are expected to stand loaded in one spot more than a normal van tyre without damage and are inflated to higher pressures than van tyres Link to comment Share on other sites More sharing options...
Brambles Posted May 12, 2009 Share Posted May 12, 2009 Camping tyres have many features improved. They can withstand overloading better (stronger reinforced tyre walls). The rubber also has a longer life, and the tread patterns are optimised better for the type of use campervans have. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted May 13, 2009 Share Posted May 13, 2009 Braunston There is now an ETRTO (European Tyre and Rim Technical Organisation) standard relating to tyres specifically intended for use on motorcaravans. When a tyre complies with that standard it can be marked "CP" (Camping Pneu) on its side-wall. As far as I'm aware ETRTO standards are not freely available online, which means that any advice on the technical aspects of CP-marked tyres will normally be based on tyre manufacturers' advertising or educated guesswork. (If anyone has access to the ETRTO 'CP' standard, I'd be keen to know exactly what it says.) These are links that refer to the benefits of current 'motorcaravan' tyres manufactured by Michelin and Continental http://www.michelin.ie/uk/front/act_affich.jsp?news_id=22237&lang=EN&codeRubrique=43 http://www.conti-online.com/generator/www/uk/en/continental/automobile_old/themes/vans/mobile/vanco_camper/vanco_camper_en.html (See also "Technical details" section on latter webpage.) Link to comment Share on other sites More sharing options...
enodreven Posted May 13, 2009 Share Posted May 13, 2009 Hi, Derek Thank you for the information and links, they are very helpful Braunston Derek Uzzell - 2009-05-13 8:34 AM Braunston There is now an ETRTO (European Tyre and Rim Technical Organisation) standard relating to tyres specifically intended for use on motorcaravans. When a tyre complies with that standard it can be marked "CP" (Camping Pneu) on its side-wall. As far as I'm aware ETRTO standards are not freely available online, which means that any advice on the technical aspects of CP-marked tyres will normally be based on tyre manufacturers' advertising or educated guesswork. (If anyone has access to the ETRTO 'CP' standard, I'd be keen to know exactly what it says.) These are links that refer to the benefits of current 'motorcaravan' tyres manufactured by Michelin and Continental http://www.michelin.ie/uk/front/act_affich.jsp?news_id=22237<=EN&codeRubrique=43 http://www.conti-online.com/generator/www/uk/en/continental/automobile_old/themes/vans/mobile/vanco_camper/vanco_camper_en.html (See also "Technical details" section on latter webpage.) Link to comment Share on other sites More sharing options...
rolandrat Posted May 13, 2009 Share Posted May 13, 2009 jhorsf, you say that the tyres with thicker side walls can be inflated to a higher pressure, my camping tyres has a maximum inflation 69 psi stamped on the side wall. When I took delivery from the dealer I went to National Tyres to check the pressures and was alarmed to see that they were inflated to 78psi, the fitter advised me to reduce the pressure to 58psi otherwise the tyres would wear badly on the centre of the tread and the suspension could suffer damage. The motorhome now drives very smoothly and the tyres run very cool. The X250 is a dream to drive with no roll whatsoever and it drives in a straight line in a high wind, I am very impressed. Link to comment Share on other sites More sharing options...
jhorsf Posted May 13, 2009 Share Posted May 13, 2009 rolandrat the max pressure and load written on sidewalls do not apply in the uk you must follow the manufacturers recommended pressures two figures are supplied max and min load most camping tyres are designed to withstand up to 5 bar some even 6.5 bar but these are c 10 ply Link to comment Share on other sites More sharing options...
Brambles Posted May 13, 2009 Share Posted May 13, 2009 jhorsf - 2009-05-13 9:55 PM rolandrat the max pressure and load written on sidewalls do not apply in the uk you must follow the manufacturers recommended pressures two figures are supplied max and min load Ermmm! 'cuse me interrupting the converstaion, but the max pressure and load on tyres most certainly does apply in the UK. . There is only one safe way to be certain you have correct pressures, have your axles weighed on a weigh bridge in running mode and laden as you would travel and ask the tyre manufacturer for recommended pressures for the axle weights. Link to comment Share on other sites More sharing options...
jhorsf Posted May 13, 2009 Share Posted May 13, 2009 the _WRITTEN max pressure and load NOT the load index figure speed rating etc http://www.dunloptyres.co.uk/ourTyres/car/sidewallMarkings/ see above letter m i think Link to comment Share on other sites More sharing options...
Brambles Posted May 13, 2009 Share Posted May 13, 2009 I am confused, thats all. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted May 14, 2009 Share Posted May 14, 2009 jhorsf May I ask you what practical understanding of motorhome tyres you have please? I'm not being rude - but it would be valuable to know whether you have expert knowledge yourself or are just relying on stuff from internet websites. Regarding the tyre sidewall-marking relating to maximum load/pressure, providing this information on a tyre may not be mandatory for tyres marketed in the UK, but the data on the tyre do still indicate the maximum load that the tyre is designed to support and the inflation pressure that is needed at that loading. I had an argument with Ford(UK)'s technical staff about this when I pointed out that the Ford data-plate on my Hobby's Transit chassis advised a 79.8psi (5.5bar) inflation-pressure for the rear tyres but the data on the tyres' sidewalls specified a maximum pressure of 70psi. I was advised that a tyre's sidewall data "Didn't count in the UK". Some time later I discovered that Ford had issued revised data-plates showing a lower rear-tyre pressure recommendation. Apparently all owners of vehicles with the 'wrong' data-plate had been sent the revised plate, but I never got one. Link to comment Share on other sites More sharing options...
jhorsf Posted May 14, 2009 Share Posted May 14, 2009 Derek Uzzell - 2009-05-14 9:36 AM jhorsf May I ask you what practical understanding of motorhome tyres you have please? I'm not being rude - but it would be valuable to know whether you have expert knowledge yourself or are just relying on stuff from internet websites. Regarding the tyre sidewall-marking relating to maximum load/pressure, providing this information on a tyre may not be mandatory for tyres marketed in the UK, but the data on the tyre do still indicate the maximum load that the tyre is designed to support and the inflation pressure that is needed at that loading. I had an argument with Ford(UK)'s technical staff about this when I pointed out that the Ford data-plate on my Hobby's Transit chassis advised a 79.8psi (5.5bar) inflation-pressure for the rear tyres but the data on the tyres' sidewalls specified a maximum pressure of 70psi. I was advised that a tyre's sidewall data "Didn't count in the UK". Some time later I discovered that Ford had issued revised data-plates showing a lower rear-tyre pressure recommendation. Apparently all owners of vehicles with the 'wrong' data-plate had been sent the revised plate, but I never got one. Derek in answer to your question no i do not just rely on the information on the internet are you saying Dunlop are wrong also? I have worked in the tyre manufacturing industry in the past for a long time If you read the answers or opinions given you will see i said the WRITTEN that is written as in WORDS not the load index speed rating etc is only there as it is manditory in some countries but not the uk and sometimes this does conflict with what the tyre manufacturer tells you and i was trying to point out that sometimes it is very confusing The best advice is to ask the tyre supplier giving them axle weights and details of your tyres and motorhome but do not be surprised if you get different answers to the same question from the (experts) Link to comment Share on other sites More sharing options...
jhorsf Posted May 14, 2009 Share Posted May 14, 2009 You can also use this email address webtyreauto@uk.michelin.com to ask Michelin a question about pressures etc dont forget to include relevant details http://www.michelin.co.uk/michelinuk/en/more/contact/20061205150539.html is the contact page website Link to comment Share on other sites More sharing options...
Chudders Posted May 14, 2009 Share Posted May 14, 2009 I have recently had much conversation with Michelin both by phone and e mail regarding the XC camping tyres and the Agilis. About 2 months ago I e mailed them my maximum permitted axle weights for my Michelin 215/75/R16 tyres with load index 113. I was advised by e mail that for the given axle weights I should use the pressures 65PSI front and 70 PSI rear. All was well I thought then I bought a set of same size Michelin Agilis and just to be sure checked with Michelin. They have now advised me that they have now had to change their advice to queries received following discussion with VOSA. They will advise of an appropriate tyre pressure for the front and adjust that figure as required. However the rear for the above size of tyres will now always be quoted as 80PSI (Yes the maximum) This applies to the XC camping and the Agilis. It appears that VOSA consider that most motorhomes run at or near the maximum load permitted at the rear and have indicated that these are the pressures they will expect at a roadside check. Michelin will not now therefore quote any other figure. A comment was also made that in the event of an accident an insurance company would expect the tyres to be at the manufacturers recommended figure. If you have Michelin tryes I would advise you to ring or e mail them with necessary details and ask for the reply in writing. I now run my rear tyres at 80PSI and was surprised that I did NOT find the ride too hard as I had expected, in fact I think the ride is better albeit perhaps a little firmer. Dave Link to comment Share on other sites More sharing options...
jhorsf Posted May 14, 2009 Share Posted May 14, 2009 Derek I had an argument with Ford(UK)'s technical staff about this when I pointed out that the Ford data-plate on my Hobby's Transit chassis advised a 79.8psi (5.5bar) inflation-pressure for the rear tyres but the data on the tyres' sidewalls specified a maximum pressure of 70psi. I was advised that a tyre's sidewall data "Didn't count in the UK kind of says it all really im sure they said the WRITTEN data not the load index speed rating etc . Link to comment Share on other sites More sharing options...
Derek Uzzell Posted May 15, 2009 Share Posted May 15, 2009 Chudders I remember you mentioning this in the following thread http://www.outandaboutlive.co.uk/forums/forums/thread-view.asp?tid=15438&posts=19 It's vital to read Mike Chapman's follow-up postings in that thread as these clarify the issue and also indicate the potential for even more confusion amongst motorcaravanners than before. Mike has had professional links to the tyre industry and undoubtedly has the most tyre-related expertise of anyone participating on this forum. (You say that you are now using 80psi in your Michelin "Agilis" tyres. As I mentioned earlier in this thread (8th posting on Page 1), there is a significant difference between "Agilis Camping" and "Agilis", with the former pattern designed to be used with an inflation-pressure up to 80psi and the latter (at least in the 217/75 R16C size with 113 load-index) design-limited to around 70psi. Presumably your tyres are "Agilis Camping"?) Link to comment Share on other sites More sharing options...
Derek Uzzell Posted May 15, 2009 Share Posted May 15, 2009 jhorsf Not sure what point you are making. I was discussing with Ford the fact that the tyres fitted in Ford's Turkish factory to my motorhome's Transit chassis had a design inflation-pressure maximum of 70psi (as shown on the tyres' sidewalls and as confirmed to me by their manufacturer Continental), but the vehicle carried a Ford-marked data-plate advising 80psi pressure for the rear tyres. There was no need to bring up load indexes or speed ratings. What irritated me was that the Ford Technical person was excusing the mistake (and let's have no doubt that it was a mistake) on the basis that, because the 70psi limit shown on the tyres was not an obligatory marking for UK-marketed tyres, it could be ignored completely. Other excuses were "It's a motorhome" and "It's a German-made motorhome". I knew full well where the 80psi figure on the Ford data-plate had originated from. The Transit FWD platform-cab chassis that became available to coachbuilt motorhome manufacturers in 2004 was initially fitted as OE with Michelin XC Camping tyres, but, by mid-2005, the chassis provided to Hobby (and to some other constructers) had 'ordinary' C-marked tyres as OE - in my vehicle's case Vanco-8s - and Ford had not altered the data-plate to reflect this. I did mention this to Ford, but it was like trying to explain tantric sex to a 3-year old. Link to comment Share on other sites More sharing options...
rolandrat Posted May 15, 2009 Share Posted May 15, 2009 Well explained Derek, what must be taken into consideration when running at very high pressures is these vehicles are coach built motorhomes with glued and screwed bodywork which in time expand and contract with the ambient temperature causing moans, groans and squeaks and loose screws. The internal furniture suffers as well. A normal commercial vehicle is designed to run at high tyre pressures because they carry heavy loads and the body work is made to withstand it. A classical example is a bus, the body rattles are all to evident even on new ones. Link to comment Share on other sites More sharing options...
colin Posted May 15, 2009 Share Posted May 15, 2009 Chudders - 2009-05-14 10:28 PM I have recently had much conversation with Michelin both by phone and e mail regarding the XC camping tyres and the Agilis. About 2 months ago I e mailed them my maximum permitted axle weights for my Michelin 215/75/R16 tyres with load index 113. IMO it's best to give actual expected axle loadings, i.e. load up and get it weighed. Link to comment Share on other sites More sharing options...
paul2 Posted May 15, 2009 Share Posted May 15, 2009 Anyone used or have any views on the Pirelli Citynet camper as they are £89.00 each on mytyres.co.uk ? Link to comment Share on other sites More sharing options...
jhorsf Posted May 15, 2009 Share Posted May 15, 2009 Paul you would be best to ask Derek Uzzell he seems to be the font of all knowledge on here and if anyone else answers you he will just ask them rude questions about how they know anything and did they just read it like he did somewhere Link to comment Share on other sites More sharing options...
Derek Uzzell Posted May 15, 2009 Share Posted May 15, 2009 jhorsf My tyre-related 'knowledge' (such as it is) comes from reading tyre-related literature - either in hard copy or on the internet -, from what I've been told when I've discussed things with tyre industry personnel, and from 40 years of driving experience. I readily admit that I have no direct practical experience of tyre manufacturing and, when I inquired about your background, that's exactly what I was hoping you might provide. Sorry you got the wrong impression - I did try not to offend! Link to comment Share on other sites More sharing options...
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