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Tyre Types and pressures


Tracker

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Following on from the payload issues we are minded to uprate the van and enjoy it without fear of being nobbled by a cash guzzling VOSA or equivalent foreign money raiser.

 

So I referred to the very useful tyre guide http://www.motorcaravanning.com/tyresafe_mh_tyres_08.pdf in order that I might become even more confused.

 

It shows pressures at various weights for light commercial and for camper tyres and the ones that interest me are.

 

CP 215/70R/15 LI 109 69 psi at 2060 kgs axle weight = 1030 kg per tyre

CP 225/70R/15 LI 112 80 psi at 2240 kgs axle weight = 1120 kg per tyre

 

LC 215/70R/15 LI 109 54 psi at 2060 kgs axle weight = 1030 kg per tyre

LC 215/70R/15 LI 112 62 psi at 2240 kgs axle weight = 1120 kg per tyre

 

So why the big difference?

 

At 69 psi the ride is already dreadful and I shudder to think what 80 psi will be like - well I know what it will be like and I don't fancy it!

 

Anecdotally LC tyres are said to give a better ride than CP tyres at the same pressures and I wonder if I can get away with LC tyres with their altogether more forgiving tyre pressures and softer sidewalls.

 

On the other hand with a rear axle weight approaching 2150 kg I need to be sure that LC tyres are up to the job.

 

Any experiences or thoughts please guys and gals.

 

PS The supplying dealer has kindly agreed to supply me with five new tyres of my choice fitted etc as he accepts that whilst the payload issue is not of his making it is not on mine either! Very kind of them I thought as it just leaves me with the air suspension and plating costs which although I could do without will not break the bank.

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I've got a headache trying to line up the screen so I can compare chart and your post, and given up,but I think you need to look again at chart, the single rear figure(which I think you've quoted) is for RWD, you need to compare single which is about same pressures
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Hi Tracker,

 

Our '04 registered Cheyenne on a Merc is plated to 3,800 kg with Front and Rear limits of 1,750 and 2,240 kg respectively.

From new it was on Conti Vanco 8 light commercial tyres and as they where just over 9 years old I have just replaced them with a brand new set of Conti Vanco 2's.

 

I think you have an error on the lower LC tyre in you post, it should be 225/70R/15 and not 215.

 

If so this is the size I have fitted and run them at 50 psi Front and 60 psi Rear and they give a very good ride, even considering we can load the rear to 2,240 kg as opposed to your 2,150 kg.

 

Hope this helps,

Keith.

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The advice provided in the tyresafe .pdf regarding CP-marked ("Camping Pneu") tyres is questionable (and some of the other data are iffy too).

 

If we start with a 215/70 R15C light commercial ('white van') tyre with a Load Index of 109 (shown wrongly in the tyresave listing as 225/70 R 15 C 109), this has a design maximum load-bearing capability of 1030kg (2060kg for a 'single-wheel' configuration axle). The tyresafe list gives 54psi as appropriate for a 2060kg axle-load, but that's way out. For this specification tyre, an inflation-pressure of around 65psi will be appropriate for a 2060kg single-wheel axle-load.

 

Moving on to CP-marked tyres...

 

These tyres are manufactured to comply with a different ETRTO standard to that relating to 'white van' tyres. The differences are summarised on the Continental website here:

 

http://www.conti-online.com/generator/www/de/en/continental/automobile/themes/van-tires/summer-tires/vancocamper/vancocamper,tabNr=3.html

 

Unless you wish to argue that there's a conspiracy between ETRTO and Continental, Michelin and Pirelli (the three companies that manufacture CP-marked tyres) I suggest you accept that CP-marked tyres differ from 'white van' tyres, in particular in their design capability to deal with a continuous load of (or beyond) the maximum defined by their Load Index. Michelin used to advise (unofficially) that its "XC Camping" tyres were designed to tolerate a load of around 10% above their Load Index datum to provide a safety reserve when the motorhome was overloaded, and I see no reason to doubt that.

 

The tyresafe data relating to the CP-marked version of a 215/70 R15 109 tyre appear to be based on Michelin's peculiar interpretation of ETRTO's advice for this tyre-type. Although the axle-load a tyre can tolerate differs according to whether the axle configuration is 'single-wheel' or 'twinned wheel' (four tyres on an axle can cope with a combined load greater than two tyres can), it's irrational to suggest that the same axle-load placed on a 'single wheel' axle should require the tyres on that axle to be inflated to radically different pressures merely because an axle happens to be a) a rear axle and b) a driven axle. If the 'single wheel' rear axle of a FWD motorhome were loaded to 2060kg, the tyresafe listing advises an inflation pressure of 69psi. But, if the rear axle is on a RWD motorhome, tyresafe advises 80psi. This is daft, and it needs to be said that Michelin's interpretation is not shared by Continental.

 

It should be expected that, at the same inflation pressure and with the same axle-load, a CP-marked tyre may produce a firmer ride that its 'white van' equivalent due to the former's more rugged carcass and stiffer sidewalls. And clearly, (for the same vehicle and axle-load) if CP tyres are inflated to 80psi and 'white van' equivalents are inflated to a pressure 15psi or 20psi lower, the ride with the CP tyres will be significantly firmer compared to the ride with the 'white van' tyres.

 

The standard tyre size for the Ford and Mercedes chassis on which motorhomes were built in the past was 225/70 R15C. Because the number of Ford/Mercedes motorhomes using that tyre-size was relatively small, Michelin (the original and, for a long time, sole manufacturer of 'camping-car' tyres) wasn't greatly interested in targeting them. Although an XC Camping tyre was available, it wasn't marketed in the UK. Consequently, the tyres fitted to Ford/Mercedes motorhomes were normally (by default) the 'white van' type. It was common to read in French motorhome magazines letters from buyers of new (particularly Mercedes-based) motorhomes complaining bitterly that their vehicles did not have "proper camping-car tyres".

 

In Tracker's case, with a rear-axle loading of 2150kg, 225/70 R15C 112 'white van' tyres should be OK. However, as his dealer will allow Tracker to choose which tyres should be fitted, the commonsense approach would be to specify CP-marked tyres and inflate them to similar pressures to those that would have been used for the 'white van' equivalents. That way Tracker would get the 'tougher' tyres without too much trade off in ride quality. I suggest Continental VancoCamper tyres, as much as anything because - if you need advice on inflation pressures - you'll nowadays get more sense from Continental than from Michelin.

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Many thanks Derek for that superb response. I appreciate and value your posting.

 

However, with several owners telling me that light commercial tyres have always worked well on their vans of similar layout and weight and the initial, and as in some cases ongoing, lack of availability or stock of some sizes of CP tyres has and continues to lead people to buy 'ordinary' van tyres I am struggling to convince myself that I really need CP tyres!.

 

So although I am inclined to play safe and opt for CP tyres I remain unconvinced that they are necessary, after all surely no manufacturer would construct and sell any motorhome with inadequate tyres for the MAM and if they, in conjunction one assumes with base vehicle and tyre manufacturers, deem LC (light commercial van) tyres to be safe why then would I not do the same?

 

Thanks again to all who have contributed,

 

Confused of King's Lynn!

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I hope Derek, you do not mind me quoting a post made many moons ago but sems very apt in helping Tracker ( and others) understand a bit more about tyres. Although written for XC camping it would apply to Agilis Camping equally as well. I think one key thing I have picked up elsewhere is you should only run a tyre up to 90% of its load carrying capacity which appears to mean for most 15 inch wheeled Motorhomes the rear is not within the recommendations if fully loaded to teh axle ratings for a load index tyre of 109, so the camping tyre is desireable as it has in effect a higher load capacity.

 

Copy of previous post........ to bewilder and confuse Mr Tracker even more... Stand clear for the pending brain explosion........

 

Derek Uzzell

 

Posted: 5 February 2005 8:19 AM

Subject: Michelin camping tyre alternatives?

 

 

 

In my final response to Norma's "Tyres" posting of 22/01/2005 I said I intended to ask Michelin about the benefits of using their XC Camping pattern tyre rather than an 'ordinary' light-commercial vehicle 10/12-ply rated alternative. This was the content of my e-mail to Michelin:

 

"In the past you have explained to me that your XC Camping pattern tyre, although 8-ply rated, essentially has the load-carrying capability of a 10-ply rated tyre and this unstated additional capacity provides a valuable 'safety margin' for those motorcaravanners unwise enough to overload their vehicles. Looking at the XC Camping data in your technical handbook, I note that this pattern is marketed in sizes most commonly used by motorhomes. Now, I can appreciate that XC Camping can provide potential advantages in those sizes where no 10-ply rated patterns are available (eg,.215/70 R 15 C). However, where an appropriate size 'genuine' 10-ply rated pattern can be obtained (eg. Agilis 101 215/75 R 16 C), is there actually any benefit in choosing XC Camping instead?"

 

I received the following reply:

 

"The use of '10 ply' would give a similar safety-factor, regarding axle weights, as implied with Michelin tread pattern XC Camping. Unfortunately, the '10 ply' mentioned is no longer listed as being available. The useable axle weights would still be limited by the vehicle 'plated' axle values. Best option may be to ensure/verify that the actual weight carried is below each 'plated' axle value, by use of a weigh-bridge, which then allows use of '8 ply' to carry the 'legal' loads."

 

OK - Let's expand on that a little.

 

Whatever sort of motorhome you own, it will normally carry a VIN-plate indicating the vehicle's maximum permitted axle loads and it's these weight restrictions that will define what tyres are suitable for it. However, same-size tyres can have a significantly different load-carrying capacity dependent on their design/construction. The tyre industry tends to talk about "ply rating" to describe a tyre's load-carrying capability. Ply-rating goes back to cross-ply tyre days and does not relate directly to the number of 'plies' (ie. layers of material) involved in a modern radial tyre's construction. Nevertheless, it's a convenient shorthand for comparing one tyre's 'strength' with another, with the higher the ply-rating figure (eg. 6-ply, 8-ply, 10-ply etc.) the greater a tyre's load-bearing capacity.

 

To the best of my knowledge, if you own a motorhome with 15" diameter wheels, the highest ply-rated tyre you can obtain is 8-ply. However, if your motorhome is SEVEL-based (Citroen/Fiat/Peugeot), there is a strong likelihood it will have been fitted from new with a 'Camping Package' that included Michelin's XC Camping tyres. As I said in my message to Michelin, XC Camping is 8-ply rated (and marked as such on the tyre side-wall) but has been designed to have equivalent load-bearing performance to a 10-ply rated tyre. This design feature provides potential benefits when a motorhome is driven habitually near (or beyond!) it's VIN-plated maximum permitted axle-loads. So, when it comes to tyre replacement time and your 'van already carries 15" XC Camping Tyres, if you weigh your motorhome in fully loaded state and find its axle loads are significantly below its VIN-plate figures, you can confidently choose an 'ordinary' 8-ply light-commercial vehicle tyre instead (eg. Agilis 81). But, if your 'van's weigh-bridge axle-load readings approach the VIN-plate maxima, you might be well advised to stay with XC Camping tyres.

 

Motorhomes (and I'm really referring to Euro-built designs here) with 16" diameter wheels are another matter as you can obtain suitable-size tyres in 8-ply, 10-ply or XC Camping patterns. The most popular 16" tyre size on more recent motorcaravans will be 215/75 R16C as fitted to the wheels of SEVEL-based 'vans using the 'Maxi' standard or Al-ko chassis and, once again, the tyres originally fitted will probably be XC Camping. Now, at replacement time, you can do as described above and take the 8-ply route (if your van's axle-loads are well within the permitted limits) or you can choose to stay with XC Camping. But the third option is to opt for a 10-ply rated tyre. Michelin advises that 215/75 R16C size is no longer available in their Agilis 101 range, but 10-ply rated tyres in this size are available from other manufacturers.

 

A bit of casual Internet trawling showed that, unlike Michelin where the ply-rating is normally apparent from the tyre name (eg. Agilis 41, 51, 61, 81 or 101), other tyre manufacturers' products are less transparent in this respect. Thus same-size tyres may be sold in different ply-rating versions but share the same name (Continental's Vanco tyre - which came out well in ProMobil's test - is an instance of this). This is something to watch out for. It also seemed that the cost differential between same-size 8-ply and 10-ply rated tyres from the same manufacturer was often not large.

 

Previous postings and press comments have mentioned the high cost of XC Camping tyres and sporadic supply problems. It would seem from the above that (at least for 16" tyres) an ordinary 10-ply rated light-commercial vehicle tyre will provide 'heavy load' motorcaravanners with a genuine alternative to XC Camping and offer possibly better road performance, cost savings and availability.

 

'Camping' tyres are now being produced by Pirelli and, I believe, other manufacturers have also expressed an interest in this specialist market. However, I've not researched what sizes are being marketed, what the ply-ratings are, or what the costs and availability are.

 

 

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Brambles:

 

That was a while ago! And, with hindsight, mixing 'camping-car', 8PR and/or 10PR tyres presents potential difficulties regarding the tyre pressures required.

 

Tracker:

 

Light-commercial vehicle tyres are tough. Michelin advises that overloading a tyre by 20% reduces its life by around 26% and MAY damage the tyre's construction, while under-inflation has a similar effect, with 20% under-inflation also reducing a tyre's life by 26%. But even a seriously under-inflated tyre will survive for a while, as I discovered when a valve partially failed on my Hobby and I drove for perhaps 80 miles with a rear-tyre pressure of 30psi rather than 60psi.

 

Michelin does not advise on over-inflation, but tyres can take plenty of it. A case mentioned on this forum years ago involved an insurance company quibbling over an accident claim where it had been discovered that a motorhome's tyres had been over-inflated (with 'white van' tyres being run at 'camping-car' pressures, if I remember correctly). The tyre manufacturer, when consulted, advised that the pressures being used - although well beyond the recommended maximum for the tyres - were still within the tyres' design 'window of safety'.

 

A rear-axle loading of 2150kg equates to a per-tyre loading of 1075kg. this is only 45kg below the maximum design load-carrying capability of a tyre with a Load Index of 112 (1120kg). Unless you've weighed your motorhome so that the load on each rear wheel is known, it's possible that the load on one of your rear tyres is already at the 1120kg figure that a 225/70 R15C 112 tyres would allow you.

 

If you are prepared to go through all the hassle of adding air-bellows, re-plating and swapping to bigger tyres, surely you should be choosing tyres that are most appropriate for your uprated vehicle? As your motorhome will normally be driven with a rear-axle load close to the replacement tyres' maximum (exactly the scenario 'camping-car' tyres are designed for) why would you choose anything other than 'camping-car' tyres?

 

If you are going to rationalise your choice based on the fact that some motorhomes (like my Hobby) have 'white van' tyres (as standard or retro-fitted) and those tyres haven't exploded, arguing that this means 'white van' tyres must be OK for all motorhomes, then fit 'white van' tyres. But, if you've the no-cost option of having 'camping-car' tyres as replacements, it would be perverse not to opt for that tyre-type.

 

The usual reason people replace 'camping-car' tyres with 'white-van' tyres is because the former are more expensive than the latter. However, if there were no price difference, I'm very doubtful that 'white-van' tyres would be selected. My Hobby was fitted with 'white-van' tyres as standard, and 'white-van' tyres were fitted when replacements were needed. But I don't operate the Hobby anywhere near axle-load or tyre-load weight maxima.

 

I was pleased to note, when I collected the Hobby from Germany, that the vehicle was wearing Continental Vanco-8 'white van' tyres, but this was because earlier Transit-based Hobbys had Michelin's prehistoric XC Camping 'camping-car' tyres as standard. If the Hobby had been fitted with, say, Michelin Agils Camping, or Continental Vanco Camper 'camping-car' tyres, I would have been just as happy.

 

Unless a motorhome's design, or the way it's being operated, makes it obvious that the heaviest-duty tyre that's available needs to be fitted, having 'white van' tyres on a motorhome is unlikely to result in a tyre-related catastrophe. On that basis, if 'camping-car' tyres did not exist, it probably wouldn't much matter. However, they do exist and, although you might believe they are not "necessary", or that you do not "really need CP tyres", as you won't be paying for them I believe it would be illogical not to opt for them.

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Thanks guys - cost is not the issue and even if I were paying it still would not be an issue.

 

There are two issues - one is safety which is paramount and the second is ride quality.

 

My recent experience of both Michelin and Conti camper tyres leaves me decidedly underwhelmed by the ride quality and bone shaking and reluctant to repeat the scenario.

 

Having a choice of 5 new tyres is a once in a lifetime opportunity which is why I am investigating.

 

Undoubtedly the dreadful and tiring ride has as much to do with the Fiat suspension as it does with tyres and hopefully semi air suspension might (or might not?) go some way to alleviating it.

 

So assuming that all tyres have a huge margin for overload protection running close to their stated limit should not be an issue - or should it - and on that basis maybe 112 LI white van tyres are just as safe as 112 LI camper tyres at around the 2150 kg weight. After all there must be plenty of 'em running all around Europe with both camper and commercial drivers blissfully unaware of the load they are supporting?

 

I probably will opt for camper tyres but more out of concern than conviction that I need 'em.

 

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It's probable that your "safety" would not be at risk if you chose white-van tyres, but, if safety is indeed paramount, camping-car tyres must be the better choice. Even if your assumption that "all tyres have a huge margin for overload protection" were correct (and I'm certain you have no data to allow you to validate that assumption), whatever margin of overload protection is built into a white-van tyre, an equivalent camping-car tyre should have more.

 

Presumably your Cheyenne currently has camping-car tyres, and I note you've been using 69psi inflation pressures (Front tyres? Rear tyres? Front and rear tyres?) You complain that the vehicle's ride is dreadful, but you've been operating the vehicle overloaded. This may well mean that (as you suggest) the hard ride results from the rear suspension design rather than from the tyres, and that (as you also say) fitting air-bellows may well improve matters. But you won't know this until you try it.

 

I'm unconvinced that camping-car tyres inflated to a pressure appropriate for the actual load being placed on them (not a one-pressure-fits-all 80psi) wiil compromise a motorhome's ride quality compared to white-van tyres. I believe you'd find that, if you swapped your present camping-car tyres for 215/70 R15C 109 white-van tyres inflated to 69psi, your Cheyenne's ride would not noticeably improve.

 

You now have a free choice between white-van or camping-car replacement tyres. I'd choose camping-car tyres myself because it's a logical no-brainer as far as I'm concerned. I would suggest, though, that if you want to choose your replacement tyres on the basis of conviction, assumption and guesswork, you'd be better off debating the issue with Jehovah's Witnesses.

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Firmly of the view that the same sized/rated CP or (non-budget) WVM tyres run at the same pressure will result in no worthwhile difference in ride quality. 

Equally of the view that ride quality can be improved by increasing the air volume, ideally achieved by more sidewall, ie going up in aspect ratio. Pick an aggressive tread, throw in a mud and snow rating, stay somewhere just north of 60psi, and be secure in the knowledge you can now drive over damp grass with impunity, and over tiny road irregularities without shaking the 'van to bits. Oh, and your speedo might even be something approaching accurate.

If you pick a decent brand and mount and maintain them properly, they won't explode.
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I picked up somehwher Tracker, you have around 1600 Kg on front axle, so wuth this weight you certainly do not need 69psi in the front and more like 60 (or less) would be correct. It is aeound 55 in theory for tyre pressure I think plus you add 10% for load under breaking and are driven wheels so 60 max. Even at max permissable front axle loading you should not need more than 60. So if you do have 60 in front it will give a harsh ride and also affect the steering stability. Not only poor directional stability because too hard but also grip will be poor in the wet when accellerating and braking. Just my penny worths again!
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Thanks Jon - I should have said that I experimented with tyre pressures before leaving and whilst we were in Germany and about 57 in the front and 65 in the back looks about right for tyre deflection and provides reasonable stability. Any less and although ride improves stability and steering suffer.

 

Hardly scientific I know but I did have some idea of what they ought to be so it was not entirely experience based guesswork - good job I always carry a good 12 v tyre inflater and reliable pressure gauge!!

 

 

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Going by the Tyresafe web page,I would gain nothing by fitting the CP type of tyre against the C  type tyre already fitted to my Motorhome.I have Continental Vanco fitted ( Originals) C 225/70 R15 C 112/110R. the Maximum rated weight for both type of tyres is the same @ 2240kgs per axle (it is the Axle weight limit were interested in) But the C tyre has a maximum tyre pressure of 65 psi  where as the CP tyre has a maximum inflation pressure of 80psi , I have a feeling I have read somewhere that the CP tyre has to be inflated to its max pressure for the Sidewalls to perform correctly ,I could stand to be corrected ,  I presently inflate my tyres to 60 psi,under the recommended maximum of 65 psi I know, but thus far covering some 4000 mile this year no Problems, the M/H came equipped with this brand of tyre,so see no reason when the time comes not to stick to the Same. and they appear to be hard wearing.
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Corky 8 - 2012-09-29 7:08 PM

 

...I have a feeling I have read somewhere that the CP tyre has to be inflated to its max pressure for the Sidewalls to perform correctly ,I could stand to be corrected..

 

I'll correct you - it's not so.

 

The pressure-to-load data relating to a tyre can be described using a simple straight-line graph. Three or four points are sufficient to allow intermediate figures to be derived.

 

The points for a tyre with a Load Index of 109 (2060kg maximum axle-load for a 'single wheel' axle) might represent 1460kg, 1660kg, 1880kg and 2060kg axle-loads on one axis, matched to (respectively) 43psi, 51psi, 58psi, and 65psi on the other axis. So, if the axle-load is, say, 1900kg, 59psi will be a suitable inflation pressure.

 

The graph of a 'white van' tyre with a 109 Load Index won't include a maximum axle-load above 2060kg and the related inflation pressure will be little higher than 65psi. The graph of a CP-marked tyre with a 109 Load Index also won't include a maximum axle-load above 2060kg, but the related inflation pressure may be given as 80psi. This practice originated with Michelin and their "XC Camping" pattern, but the 80psi is a 'can-be-inflated to' datum not a 'must-be-inflated to' figure.

 

Think about what you've written and, if true, how it would apply to Tracker's situation. In his case, while it might be understandable (because, even with larger tyres, his motorhome's rear-axle load will be near the tyres' design maximum) to inflate CP-marked tyres on his Cheyenne's REAR axle to 80psi, his motorhome's FRONT axle will be carrying a much lower load and, consequently, a significantly lower inflation pressure can safely be used. If the sidewalls of CP-marked tyres did not "perform" correctly unless the tyres were not inflated to 80psi, 80psi would need to be used irrespective of the load being placed on the tyres.

 

In your case, if your motorhome's axle-load is 2240kg and Continental recommends an inflation pressure of 65psi for that loading, then 60psi is 5psi too low. On the other hand, if your motorhome's axle-load is, say, 2000kg , then an inflation pressure of 60psi will be appropriate.

 

 

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Derek Uzzell - 2012-09-30 9:36 AM
Corky 8 - 2012-09-29 7:08 PM...I have a feeling I have read somewhere that the CP tyre has to be inflated to its max pressure for the Sidewalls to perform correctly ,I could stand to be corrected..
I'll correct you - it's not so.The pressure-to-load data relating to a tyre can be described using a simple straight-line graph. Three or four points are sufficient to allow intermediate figures to be derived.The points for a tyre with a Load Index of 109 (2060kg maximum axle-load for a 'single wheel' axle) might represent 1460kg, 1660kg, 1880kg and 2060kg axle-loads on one axis, matched to (respectively) 43psi, 51psi, 58psi, and 65psi on the other axis. So, if the axle-load is, say, 1900kg, 59psi will be a suitable inflation pressure.The graph of a 'white van' tyre with a 109 Load Index won't include a maximum axle-load above 2060kg and the related inflation pressure will be little higher than 65psi. The graph of a CP-marked tyre with a 109 Load Index also won't include a maximum axle-load above 2060kg, but the related inflation pressure may be given as 80psi. This practice originated with Michelin and their "XC Camping" pattern, but the 80psi is a 'can-be-inflated to' datum not a 'must-be-inflated to' figure. Think about what you've written and, if true, how it would apply to Tracker's situation. In his case, while it might be understandable (because, even with larger tyres, his motorhome's rear-axle load will be near the tyres' design maximum) to inflate CP-marked tyres on his Cheyenne's REAR axle to 80psi, his motorhome's FRONT axle will be carrying a much lower load and, consequently, a significantly lower inflation pressure can safely be used. If the sidewalls of CP-marked tyres did not "perform" correctly unless the tyres were not inflated to 80psi, 80psi would need to be used irrespective of the load being placed on the tyres.In your case, if your motorhome's axle-load is 2240kg and Continental recommends an inflation pressure of 65psi for that loading, then 60psi is 5psi too low. On the other hand, if your motor home's axle-load is, say, 2000kg , then an inflation pressure of 60psi will be appropriate.[/Q 

Derek, Thank you for Clarifying in such an easy to follow way , the sidewall situation,I stand Corrected,

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Tyre construction seems to be a bit of a black art!

 

http://www.conti-online.com/generator/www/uk/en/continental/automobile/themes/van-tyres/standard-van-tyres/vancocamper/vancocamper/vancocamper,tabNr=3.html

 

That link maybe begins to explain what CP tyres are all about - although I still can't see what all the fuss is about and why makers go to all that trouble for a motorhome only market segment when a light commercial tyre would seem to do the job very well.

 

Can LC (light commercial or white van man) tyres really be inferior to CP (camping pneu) tyres?

 

If the sidewalls and construction are stiffer then I don't see how the ride can be the same between the two.

 

I know the two are quite different but anyone who has experienced the harsh ride given by stiff side walled run flat tyres when combined with firm suspension (like BMW) might well know how tiring it can be and I can't help but compare stiff walled CP tyres with run flats?

 

Surely when it comes to overload and general abuse white van man, builders, and hauliers are just as abusive and careless - if not more when often the drivers don't pay for new tyres themselves - to their tyres as motor caravanners so would there not be as a good safety margin in both types?

 

I understand the difference and I will probably go for CP tyres (even if I where paying for them myself) if for no other reason than they are available - but I am far from convinced!

 

Next question - which ones - Continental, Michelin or Pirelli - or is there very little difference on the road between all three?

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Tracker - 2012-09-30 11:55 AM

 

...Next question - which ones - Continental, Michelin or Pirelli - or is there very little difference on the road between all three?

 

Visiting the 3 manufacturers' websites suggests that the only CP-marked tyre in the size you are looking for (225/70 R15C) may be Michelin's "Agilis Camping" pattern.

 

(If you really hanker after 'white-van' tyres and are unconvinced that 'camping-car' tyres are no better safety-wise and may adversely affect your motorhome's ride quality, why don't you just opt for 'white-van' tyres rather than keep asking endless (and essentially unanswerable) questions about their potential pros and cons? Surely it can't be that difficult a decision to make?)

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Tracker, you mentioned buying five tyres, why not go for 4 Michelin Agilis camping ( as Derek suggests Michelin are the only CP tyres in your size and I will add are M+S rated) which are probably what you have fitted at present, and use the best one as your spare. A spare is just that a spare and may never be needed and if so you can always run slower on it until puncture is repaired because it is older. Then you will save the cost of one tyre meaning you would be much the same price as 5 good premier LC van tyres. problem solved. 4 Michelin Agilis camping it shall be. Good tyres, M+S rated, strongest tyre available, good wear properties, excellent characteristics, wear, and grip. (Completely different beast from their old outdated XC tyres). Food for thought but it is what I would I do.
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Derek Uzzell - 2012-09-30 6:56 PM

(If you really hanker after 'white-van' tyres and are unconvinced that 'camping-car' tyres are no better safety-wise and may adversely affect your motorhome's ride quality, why don't you just opt for 'white-van' tyres rather than keep asking endless (and essentially unanswerable) questions about their potential pros and cons? Surely it can't be that difficult a decision to make?)

 

I value your input Derek, usually, but if I am boring you there is no obligation to respond.

 

I thought that I was asking questions that might also be of interest to other people and judging by some of the postings I was not so wrong about that.

 

Forking out five hundred quid plus for tyres when one has an absolute freedom of choice is a rare event and it seemed to be as good a topic as any other for discussion?

 

I can't speak for others but I am learning from this thread and if it goes some way to making us all safer and more comfortable it won't have been an utter waste of anyone's time will it?

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Derek

This thread has covered the 3 tyre aspects of Camper v Light Commercial , 8/10 ply and appropriate pressures. Your responses are brilliant but at the risk of asking the obvious, may I focus on the pressure question and check what pressures you think I should use? I have a Swift Sundance 590RS on Michelin 215/70 R15 CP 109. My ‘van is plated for Front: 1.85kg and Rear: 2.00kg. If I use the graph axis figures in your reply of 30 Sept (did you mean 1860 rather than 1880 typed?) does it mean my tyre pressures should be Front: 59 and Rear: 63?

Brambles mentioned adding 10% to adjust for braking and driving wheels. My ‘van is a Fiat FWD so should I make an adjustment of 10% to the front tyres and a smaller addition to the rear or is such adjustment unnecessary using your figures?

Thanks JohnK

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RE: "Camping" tyres v "White van" tyres..

 

I'd always assumed that the only reason folk opted for "white van" tyres over "CP" tyres was because they were cheaper,(.. and/or possibly, were all that was available at the time... )..

 

..and as Tracker had previously said that the dealer is going to be sorting them out AND paying for them,I can't really see why anyone would choose the "non-campingcar" tyres... :-S

(..unless,perhaps, they were looking for something more "knobbly" ?...)

 

Personally,in Tracker's case,if this rear axle is as "unworkable" as he say,I'd be fireing it back at the dealer and insisting that he also sorted out the rear springs(air assistors?)and any SVtech documentaion....

 

 

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