Pablo79 Posted March 12, 2021 Share Posted March 12, 2021 Hi all, After much research I decided on getting some Agilis Crossclimates to replace my Agilis campers. Many positive reviews online from other motorhomers, same load rating (118), same size, and so on. The campers don't feel great, so I'm happy for the change! They were due to come tomorrow to fit, but the fitter from kwikfit just called and said I shouldnt fit them, as the recommended tyre pressure for my vehicle is 79psi, and the Cross Climates are 76psi max. I asked him to explain what the issue was as the size and load were correct, and he said different tyres run at different pressures, but he wasn't really able to tell me why I can't run these. He just said, they're not campers and the tyre pressure is different. So I'm a bit stuck! Any views from the forum? Link to comment Share on other sites More sharing options...
Brian Kirby Posted March 12, 2021 Share Posted March 12, 2021 Have you checked/verified what the maximum tyre inflation pressures are for your van, and for the Michelin Agilis Crossclimate tyres of the size required? If the fitter is correct with the pressures he quoted, I think he is right. He would be negligent to supply and fit tyres that are inadequate for the requirements of the vehicle, in this case an inflation pressure of 79psi. The result would be over-inflated tyres. Link to comment Share on other sites More sharing options...
Pablo79 Posted March 12, 2021 Author Share Posted March 12, 2021 Thanks Brian. I've noticed that you're quick to reply to most threads on here! Are you head honcho? Link to comment Share on other sites More sharing options...
BruceM Posted March 12, 2021 Share Posted March 12, 2021 Out of interest, what pressures does your van’s manual say you should be running your tyres at? Link to comment Share on other sites More sharing options...
Brian Kirby Posted March 12, 2021 Share Posted March 12, 2021 Pablo79 - 2021-03-12 5:28 PM Thanks Brian. I've noticed that you're quick to reply to most threads on here! Are you head honcho? No way Hosé! :-D Link to comment Share on other sites More sharing options...
Derek Uzzell Posted March 12, 2021 Share Posted March 12, 2021 Details of a 2017 Benimar Mileo 243 motorhome are given here https://motorhomesltd.com/product/benimar-mileo-243-2017/?wpp_export=pdf The vehicle will have been built on a Ducato ‘light’’ (3500kg) chassis but came as standard with 16” alloy wheels (mentioned in Pablo79’s posting here) https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Ducato-Alloy-Wheels/57700/ so the tyres will have been Michelin Agilis Camping with a 225/75 R16CP specification, and the recommended tyre pressures will have been 5.5bar (80psi) for the rear tyres and either 5.0bar(72.5psi) or 5.5bar for the front tyres. The Michelin Agilis “Crossclimate” tyre is described here https://www.michelin.co.uk/auto/tyres/michelin-agilis-crossclimate# It has a directional tread pattern and the reviews are not all positive... Link to comment Share on other sites More sharing options...
Pablo79 Posted March 12, 2021 Author Share Posted March 12, 2021 KwikFit main office called me back and said the tyres are fine for my vehicle. My MH suggests 79psi ±1. I wanted the 3 peak marking for my planned travels, and the camper tyres don’t meet this. The CCs are 76psi max. Kwik fit said they need to advise of the slight difference, but in practical terms the tyres are more than suitable and they have fitted them to lots of MHs Link to comment Share on other sites More sharing options...
TeamRienza Posted March 12, 2021 Share Posted March 12, 2021 I think with a small margin of 3psi I would be inclined to ask Michelin directly. You have two conflicting answers from Kwik fit, both verbal. I would not feel content with that. Davy Link to comment Share on other sites More sharing options...
rayc Posted March 12, 2021 Share Posted March 12, 2021 Pablo79 - 2021-03-12 4:46 PM Hi all, After much research I decided on getting some Agilis Crossclimates to replace my Agilis campers. Many positive reviews online from other motorhomers, same load rating (118), same size, and so on. The campers don't feel great, so I'm happy for the change! They were due to come tomorrow to fit, but the fitter from kwikfit just called and said I shouldnt fit them, as the recommended tyre pressure for my vehicle is 79psi, and the Cross Climates are 76psi max. I asked him to explain what the issue was as the size and load were correct, and he said different tyres run at different pressures, but he wasn't really able to tell me why I can't run these. He just said, they're not campers and the tyre pressure is different. So I'm a bit stuck! Any views from the forum? The recommended tyre pressure of 79psi is only for the specified tyres i.e. CP ones of the size stipulated on the plate. If the tyres were changed to a C type tyre for example the pressure would need to be as per the replacement tyre load table. Link to comment Share on other sites More sharing options...
Pablo79 Posted March 12, 2021 Author Share Posted March 12, 2021 I feel content. The first chap, the fitter, wasn’t comfortable but he couldn’t explain in detail why. It was him that sought the second opinion and asked them to call me. The person who followed up was knowledgable and confident. While ultimately it was my decision given that the specs were marginally out, he said these tyres are superior and are suitable for the intended use. Between this forum and the other one, there’s an awful lot of chat about tyre choices and pressures! It makes for good reading, but also shows there’s clear brand loyalty or the opposite :) Thanks for the comments all. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted March 13, 2021 Share Posted March 13, 2021 Using Michelin “CrossClimate” tyres on motorhomes was mentioned (by me) in this late-2019 forum thread when versions of that tyre became available with sizes and load-carrying capability that were suitable. https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Winter-tyres-3PMSF/53364/ Personally, I wouldn’t choose them if i wanted a tyre that was 3PMSF-marked simply because of their directional tread pattern. There are ‘all season’ alternatives (eg. Continental’s VanContact 4Season) that have a non-directional symetrical tread pattern and 3PMSF marking, and these would not present potential ‘emergency’ fitting problems is a spare wheel were being carried. If a ‘camping-car’ tyre is required, Continental’s VanContact Camper is CP and 3PMSF marked and has a non-directional symetrical tread pattern. Plainly, if the tyres fitted to a motorhome have a potential load-carrying capability well in excess of the vehicle’s maximum axle-loads (or its measured ‘operating’ axle loads) whatever the type of tyre if unnecessarily high inflation pressures are used it should be anticipated that the vehicle’s ride quality will suffer badly. I would have thought that a normally operated Benimar Mileo 243 motorhome fitted with 225/75 R16CP tyres and using 5.5bar (80psi) inflation pressures would have the ride quality of a Poundland skateboard. Just becaise a tyre can tolerate a high load and a high inflation pressure doesn’t mean that the tyre HAS to be run at its maximum design pressure if the load it is carrying does not justify this. Link to comment Share on other sites More sharing options...
Pablo79 Posted March 13, 2021 Author Share Posted March 13, 2021 Derek Uzzell - 2021-03-13 7:38 AM I would have thought that a normally operated Benimar Mileo 243 motorhome fitted with 225/75 R16CP tyres and using 5.5bar (80psi) inflation pressures would have the ride quality of a Poundland skateboard. Just becaise a tyre can tolerate a high load and a high inflation pressure doesn’t mean that the tyre HAS to be run at its maximum design pressure if the load it is carrying does not justify this. This is how the agilis campers feel! Link to comment Share on other sites More sharing options...
Derek Uzzell Posted March 13, 2021 Share Posted March 13, 2021 Well they would wouldn’t they... My 2015 Rapido 640F motorhomes has Michelin Agilis Camping tyres (215/70 R15CP) and, although shorter than your Benimar, the vehicle has a similar Fiat Ducato camping-car chassis. Rapido advises ‘when fully loaded’ tyre pressures of 5.0bar (front tyres) and 5.5bar (rear tyres). When lightly loaded - which is how I operate the motorhome - the vehicle’s ride quality is bone-shaking at those pressures, so I use lower pressures that are still well above the loads being placed on the Rapido’s axles but do noticeably improve the ride quality. If you operate the CrossClimate tyres at pressures similar to what you’ve being using for the Agilis Camping tyres, you should anticipate that the ride quality will be similarly harsh. Link to comment Share on other sites More sharing options...
DavyS Posted March 13, 2021 Share Posted March 13, 2021 I have a similar vehicle with Continental van tyres. After visiting a weighbridge and getting the axle weights, Continental recommended somewhere between 3 to 3.5 bar, ie. 45 - 50 psi. So I run at 50psi all round, the van drives much more comfortably at those pressures. I think if I used 79psi the din from rattles would be intolerable and the steering far too light. Link to comment Share on other sites More sharing options...
Pablo79 Posted March 13, 2021 Author Share Posted March 13, 2021 Out of curiosity, do you all run at the recommended levels (in my case 79) all round, or do you adjust for comfort, knowing you’re below what’s recommended? The fitter today was saying you can run below the recommended pressure, but the tyres will generate more heat, wear more, and so on. I find it interesting that the recommended tyre pressure is the same whatever the load too Link to comment Share on other sites More sharing options...
stevec176 Posted March 13, 2021 Share Posted March 13, 2021 I used to run my Rapido at recommended pressures until I fitted Tyrepal and went to Spain in 2019. I was constantly having to cancel the warning alarms for over inflation as the indicated pressures were over 90psi. I now run at 55 front 60 rear and all well. Link to comment Share on other sites More sharing options...
Brian Kirby Posted March 13, 2021 Share Posted March 13, 2021 Pablo79 - 2021-03-13 11:10 AM Out of curiosity, do you all run at the recommended levels (in my case 79) all round, or do you adjust for comfort, knowing you’re below what’s recommended? The fitter today was saying you can run below the recommended pressure, but the tyres will generate more heat, wear more, and so on. I find it interesting that the recommended tyre pressure is the same whatever the load too Most tyre manufacturers will recommend optimum pressures for their tyres to match actual axle loads. The exception is Michelin, which will only recommend optimal pressures for front tyres for their "CP" rated tyres. However, to benefit from the lower optimal pressures, you first have to establish the actual axle loads for your van when fully laden. This is only possible by taking the fully laden van to a weighbridge and getting its actual axle loads. Under-inflation is potentially dangerous, as under-inflated tyres overheat and overheated tyres are prone to catastrophic failure! A little over-inflation, OTOH, only results in a harsh ride and somewhat unsatisfactory handling. The motorhome manufacturer cannot know how his eventual client will load his van, so can only safely recommend tyre pressures suited to the maximum permissible axle loads. Were both axles to be loaded to their maximum permitted load, the vehicle would exceed its legally permitted MAM, so these pressures inevitably result in over-inflation relative to the actual load on at least one axle (possibly both), but that is the fail-safe state until the actual "in use" axle loads are known. Link to comment Share on other sites More sharing options...
Derek Uzzell Posted March 13, 2021 Share Posted March 13, 2021 Pablo79 - 2021-03-13 11:10 AM Out of curiosity, do you all run at the recommended levels (in my case 79) all round, or do you adjust for comfort, knowing you’re below what’s recommended?... It might be revealing to know the percentage of owners of Ducato-based coachbuilt motorhomes fitted wit CP-marked (‘camping-car’) tyres that inflate those tyres to 5.0/5.5bar (15” wheels, front and rear respectively) or 5.5bar (16” wheels, front AND rear). This issue goes back over 20 years to when Michelin first marketed the XC Camping range. Initially 5.5bar (80psi) was advised by Michelin only for XC Camping tyres on the rear wheels of motorhomes being driven in Continental Europe, then Fiat started to provide manufacturers of coachbuilt motorhomes with Ducato chassis that had a ‘Camping-Car Pack’ that included Michelin XC Camping tyres - and that’s when high inflation pressures for front and rear tyres began to be generally recommended. Over time the high inflation pressures for ‘camping-car’ tyres (that eventually began to be marked “CP” (Camping Pneu) to indicate the type of vehicle they were aimed at) became more and more set in ston. The ETRTO got involved and advised that motorhomes should have CP-marked tyres and that 5.5bar should be the pressure to use for a motorhome’s rear tyres. It’s the ETRTO’s diktat that Michelin adheres to and (as Brian has just said) why Michelin will advise only 5.5bar for rear tyres irrespective of a motorhome’s specification or measured axle-loadings. (Continental are more accommodating and, in any case, the necessary inflation-to-weight data are available in Continental online documentation.) Link to comment Share on other sites More sharing options...
Pablo79 Posted March 13, 2021 Author Share Posted March 13, 2021 Derek Uzzell - 2021-03-13 2:10 PM It might be revealing to know the percentage of owners of Ducato-based coachbuilt motorhomes fitted wit CP-marked (‘camping-car’) tyres that inflate those tyres to 5.0/5.5bar (15” wheels, front and rear respectively) or 5.5bar (16” wheels, front AND rear). This doesn't surprise me. If the vehicles state the pressures should be X front and rear, why wouldn't they do it? I was just looking my car to see what that said... the door sticker gives different pressures if the car is stuff full of humans than it does if just two. The van just says one pressure, whatever's in it, and the same for F or R. Link to comment Share on other sites More sharing options...
costaexpress Posted March 13, 2021 Share Posted March 13, 2021 Pablo79 - 2021-03-13 11:10 AM Out of curiosity, do you all run at the recommended levels (in my case 79) all round, or do you adjust for comfort, knowing you’re below what’s recommended? The fitter today was saying you can run below the recommended pressure, but the tyres will generate more heat, wear more, and so on. I find it interesting that the recommended tyre pressure is the same whatever the load too My van has a sticker saying 79 front and back. I run 67 back and 62 front. It iseems to provide a reasonable ride, although still a little hard. Continental produce a tyre/weight chart and according to that I could run lower pressures, however, something holds me back from going lower (age I think, I'm sure I wouldn't have even checked them a few years ago). Link to comment Share on other sites More sharing options...
Derek Uzzell Posted March 13, 2021 Share Posted March 13, 2021 Pablo79 - 2021-03-13 2:15 PM Derek Uzzell - 2021-03-13 2:10 PM It might be revealing to know the percentage of owners of Ducato-based coachbuilt motorhomes fitted wit CP-marked (‘camping-car’) tyres that inflate those tyres to 5.0/5.5bar (15” wheels, front and rear respectively) or 5.5bar (16” wheels, front AND rear). This doesn't surprise me. If the vehicles state the pressures should be X front and rear, why wouldn't they do it? I was just looking my car to see what that said... the door sticker gives different pressures if the car is stuff full of humans than it does if just two. The van just says one pressure, whatever's in it, and the same for F or R . I think you may have misinterpreted the thinking behind my post. Given the number of complaints and questions there have been on motorhome forums about the harsh ride of Ducato-based models fitted with ‘camping-car’ tyres when using the high recommended inflation pressures, I’d be a mite surprised if many owners use those pressures (or if they continue to use them after they’ve owned the motorhome for a while). Brian Kirby’ advice - weigh the fully-laden motorhome’s axle loads and (based on the data obtained) adjust the tyre pressures sympathetically - must have been repeated scores of times on all the major forums during the last 20 years. Link to comment Share on other sites More sharing options...
Pablo79 Posted March 13, 2021 Author Share Posted March 13, 2021 Derek Uzzell - 2021-03-13 2:41 PM Pablo79 - 2021-03-13 2:15 PM Derek Uzzell - 2021-03-13 2:10 PM It might be revealing to know the percentage of owners of Ducato-based coachbuilt motorhomes fitted wit CP-marked (‘camping-car’) tyres that inflate those tyres to 5.0/5.5bar (15” wheels, front and rear respectively) or 5.5bar (16” wheels, front AND rear). This doesn't surprise me. If the vehicles state the pressures should be X front and rear, why wouldn't they do it? I was just looking my car to see what that said... the door sticker gives different pressures if the car is stuff full of humans than it does if just two. The van just says one pressure, whatever's in it, and the same for F or R . I think you may have misinterpreted the thinking behind my post. Given the number of complaints and questions there have been on motorhome forums about the harsh ride of Ducato-based models fitted with ‘camping-car’ tyres when using the high recommended inflation pressures, I’d be a mite surprised if many owners use those pressures (or if they continue to use them after they’ve owned the motorhome for a while). Brian Kirby’ advice - weigh the fully-laden motorhome’s axle loads and (based on the data obtained) adjust the tyre pressures sympathetically - must have been repeated scores of times on all the major forums during the last 20 years. Gotcha. It's great advice and I'll be doing it soon! Link to comment Share on other sites More sharing options...
Brian Kirby Posted March 13, 2021 Share Posted March 13, 2021 When we got our first van in 2005 it was possible to 'phone Michelin technical, advise them of the axle loads, and they would tell you over the phone what pressures they would recommend for the XC Camping tyres Derek mentions above. If I remember correctly, this soon changed to e-mail, so that Michelin could prove what they had been told, and what they had said. I can't remember the source of this, but I then learned that Michelin had become aware that motorhomers were overloading their rear tyres. Whether this was simply because they had "imagineered" the rear axle load, and been given a corresponding lower rear axle tyre pressure, or whether they hadn't realised that what they had piled into their vans could possibly overload it (all those inviting lockers and cupboards!) wasn't clear, but as a result, there had been a number of rear tyre blow-outs with, I assume, catastrophic consequences, that the company considered potentially damaging to their reputation. So, they quite abruptly ceased advising pressures for load for rear axle tyres. Speculating, the ETRTO may just have picked up on this news and advised tyre manufacturers against quoting pressures for motorhome rear axle load, or Michelin might have advised the ETRTO of their experiences, so prompting the ETRTO to advise against doing so, conveniently justifying Michelin's abrupt withdrawal of that advice. Where I picked that bit up I can't remember. It could have been the nice helpful chap at Michelin letting an indiscreet cat out of its bag, or it might possibly have been something Derek wrote in recounting a conversation he'd had with a Michelin Technical rep at a motorhome show (I assume Derek will be able to remember if the latter! :-)). What is interesting, though, is that Continental continue to give advice on pressures for load on rear axles fitted with their CP rated tyres. It is also interesting to note that the latest edition of the "Motorhome Tyres And Your Safety" booklet "published by tyresafe.org" contains this statement: "for CP-type tyres when fitted in a single formation on a motorhome rear axle, set the inflation pressure to 5.5 bar (80 psi) for all loads". This rider is absent from earlier editions of the booklet. Our van has 225/75/R/16CP 116 Michelin Agilis tyres, for which, because these tyres are fitted, the recommended rear tyre pressure is 5.5 bar for a rear axle load of 3,500kg. The rear axle is actually plated at 2,400kg (standard "Maxi" chassis). The actual laden rear axle load +10% is 1,881kg. I use the nearest higher pressure recommended in the above Tyresafe booklet (disregarding the above rider!), which corresponds exactly with the pressure recommended by Continental for their equivalent 225/75/16 116 CP tyre at the same load in their 2020/21 Databook. This is my choice, and it is not 5.5 bar! :-D Link to comment Share on other sites More sharing options...
witzend Posted March 13, 2021 Share Posted March 13, 2021 Pablo79 - 2021-03-12 4:46 PM They were due to come tomorrow to fit, but the fitter from kwikfit just called and said I shouldnt fit them, as the recommended tyre pressure for my vehicle is 79psi, and the Cross Climates are 76psi max. So I'm a bit stuck! Any views from the forum? I'd ask him where I'd find a tyre pressure gauge that's accurate to 3 psi +/- and not give it another thought Link to comment Share on other sites More sharing options...
Keithl Posted March 13, 2021 Share Posted March 13, 2021 witzend - 2021-03-13 5:11 PM I'd ask him where I'd find a tyre pressure gauge that's accurate to 3 psi +/- and not give it another thought If you buy a reasonable quality tyre pressure gauge quoted as being accurate to 'GS/TUV Approved and ANSI Grade B accuracy' then this will be accurate to +/- 2% over the mid 50% of its range. eg Something like this https://www.amazon.co.uk/RACE-RX0014-Tyre-Pressure-Gauge/dp/B000VZ8S26 Keith. Link to comment Share on other sites More sharing options...
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