# Are you using CP rated tyres?



## pete4x4 (Dec 20, 2006)

Ive just changed my tyres for Michelin Agilis CrossCountry tyres, they are new and meet the load requirements for my Bailey moho.
As the max pressure is 65psi I asked Michelin what pressures I should be running, they have comeback with pressures but also that they are not CP rated so do not meet the ETRTO directive on motorhome tyres and as such cannot recommend them as a motorhome tyre although they go out of there way to say that they are safe to use.


Apparently us motorhomers cant be trusted not to overload our vans and as such the CP rated tyre is designed to be heavily abused by including a safety margin.


CP tyres are only available from Michelin, Continental and Pirelli so limited choice of 3 tyres.


The CrossClimates are almost an all terrain tyre very good in the wet and snow and grass apparently.


So Michelin have offered to change my tyres back to a Camping tyre if I want foc as there website is misleading but I dont really want to change, so is anybody else running commercial van tyres succesfully?


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## shingi (Apr 18, 2008)

I know many MH'ers do use commercial van tyres, as the question does crop up occasionally on MHF. Personally I stick with CP rated tyres as I have no wish to give any insurance company some "get out" excuse if things should go wrong. You takes your choice as they say!!


Mick


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## trek (May 1, 2005)

I have a 5 ton Motorhome running on standard commercial / van tyres ( and that included the originals when camper was new)

In fact there are no CP tyres available from any manufacturer in my size 205/75R16

Currently running michelin agilis alpin ( winter tyres) Local ambulances running on same throughout summer as too some asda / ocardo vans


Apart from cost as they are new to market the michelin cross climate i think should make a fantastic camper tyre


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## trek (May 1, 2005)

By the way i run my camper tyres at the pressures shown by the chassis manufacturer for fully a laden vehicle 


As a matter of interest what valves have been fitted , standard rumbee of metal valves .?


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## dghr272 (Jun 14, 2012)

Rubber valves are available for higher pressures now, my Arapaho has been running on the correct weighted commercial tyres fine for three years now, I also had the high pressure rubber valves fitted as the metal valves were reacting with the rims causing slow deflation. I agreed to the rubber valves on the recommendation of the fitters as the same valves are fitted to the ambulances the tyre supplier is contracted to keep on the road at 80psi.

Terry


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## 747 (Oct 2, 2009)

I have CP Agilis on the front but recently renewed the 4 rear tyres with Agilis Commercial tyres. They have the same load rating but are not S&M rated like the CP. Each rear Tag Axle is only rated at 1500Kg so I saw no reason to fit CP as they run at a lower pressure anyway. I fitted new steel valves.


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## pete4x4 (Dec 20, 2006)

I have steel valves, I couldnt run at the chassis pressure as its 15psi over the max pressure of the cross climate which is 65psi which is what Michelin recommended for my tyre size and load.


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## pete4x4 (Dec 20, 2006)

shingi said:


> I know many MH'ers do use commercial van tyres, as the question does crop up occasionally on MHF. Personally I stick with CP rated tyres as I have no wish to give any insurance company some "get out" excuse if things should go wrong. You takes your choice as they say!!
> 
> Mick


Yep I agree but I have a statement from Michelin stating they are perfectly safe and suitable but will not recommend due to the fact that motorhomers overload. So no get out there for an insurance company as long as i'm not overloaded of course


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## Mrplodd (Mar 4, 2008)

So long as whatever tyres fitted have an equivalent (or higher) load and speed rating then there is clearly no problem. I always replaced my MH tyres with commercial van ones (of equivalent load and speed ratings) because not only were they similarly rated but they were also MUCH cheaper.

I know some will claim the CP tyres are "stronger" but I struggle to see how they can be as they have the* same* load rating as van tyres. If the van tyres were not "as strong" then they would surely have a lower load rating to reflect that?

Personal choice of course.

Andy


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## rayc (Jun 3, 2008)

Are Transit based motorhomes which are supplied fitted with C tyres e.g Chaussons, less safe than Fiat ones fitted with CP tyres?


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## dghr272 (Jun 14, 2012)

Mrplodd said:


> So long as whatever tyres fitted have an equivalent (or higher) load and speed rating then there is clearly no problem. I always replaced my MH tyres with commercial van ones (of equivalent load and speed ratings) because not only were they similarly rated but they were also MUCH cheaper.
> 
> I know some will claim the CP tyres are "stronger" but I struggle to see how they can be as they have the* same* load rating as van tyres. If the van tyres were not "as strong" then they would surely have a lower load rating to reflect that?
> 
> ...


Spot on Andy, I worked 8 years in a Michelin factory manufacturing tyres actually in the making process, Camper tyres have an extra layer of carcase belting applied to help protect the sidewall, although it didn't help the CP tyres originally fitted to my motorhome that cracked badly, but as you say the ratings are the key for everyone.

I firmly believe like everything related to motorhomes manufacturers just screw you for as much as they can.

Terry


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## Pudsey_Bear (Sep 25, 2008)

I was going to ask what CP tyres were, never having noticed, but felt I would get crap for not knowing, so looked it up, and found a lot of info possibly a few of us don't know.

Knock yourselves out

https://www.mytyres.co.uk/tyre-glossary.html


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## Mrplodd (Mar 4, 2008)

Below is the text from Kev’s link that refers to CP tyres. I post it without comment other than to wonder just how old the info is? They refer to “Mobile Homes” which are VASTLY different things compared to Motorhomes or Camper vans. :wink2:

CP Tyres

CP tyres have been developed for camping vehicles such as mobile homes and are fitted with a reinforced sub structure. Equivalent to C tyres in terms of construction, CP tyres therefore have a high load bearing capacity. Due to considerably higher air pressure, CP tyres have higher load bearing capacity and at the same time, greater protection from mechanical damage. This reinforcement is done over several layers as in 205/55 R16 99 CP V tyres. This protects the tyres during a long stationary period on a base plate.
Caution: RF-/XL tyres and LT tyre are not C tyres, even if they resemble them with regard to size and load index. Therefore you should check the paperwork for your vehicle or ask the manufacturer which tyres you can use.
In contrast, the abbreviation “CP” stands for “Camping”. This refers to C tyres which are optimised for the particular requirements of mobile homes, such as long standing times.

Andy


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## pete4x4 (Dec 20, 2006)

Thats a reasonable definition of a CP tyre and is what Michelin quoted to me, however it looks like Continental Camper tyre is no longer available in my size so they maybe dropping the range and the CrossClimate comes with extra sidewall protection to prevent kerbing and the pressure from higher loads.


So as far as I can tell its only the standing for long periods that arent covered.


Both Michelin and Continental both say for use up to the max load specified so I dont get the extra stability from being able to run at 80psi 5.5 bar which just makes it an uncomfortable ride. Running at 65psi is noticeably different no rattles yet tyre deflection remain the same as far as I can tell.


Thank you all for your views so far.


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## Pudsey_Bear (Sep 25, 2008)

Thanks Andy, I left it as a link as there is a whole host of tyre info in there which may benefit everyone.


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## Mrplodd (Mar 4, 2008)

Kev

Appreciate that but not everyone is happy “clicking through” !

Andy


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## Pudsey_Bear (Sep 25, 2008)

Yes, I forget a lot don't trust links.


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## Penquin (Oct 15, 2007)

Interesting discussion we use CP rated tyres simply as I would not want to give the insurers any wringgle room. We have fitted the tyres originally recommended by the manufacturer for the simple reason that they are the most compatible.

I considered van tyres constitute but discovered that here in France that would breach the Law and give the insurers the ability to reject any claim.

I was aware that CP tyres have more layers because of the way that many MotorHomes sit still for large parts of the year and are subject t UV damage which may weaken the wall structure so that extract reinforces why I believe CP tyres are the most suited for our use. I am aware that there is a difference in cost but very few MH owners wear their tyres out AFAIK - most are replaced because they have reached a date arbitrarily arrived at probably beyond which manufacturers are less confident in their products. Having said that our tyres get a thorough inspection (and I mean thorough) whenever we go for a CT (MoT equivalent) and he is the one that says that tyre can or cannot continue to be used. His neck is therefore also on the line if there is a problem within the time before the next CT.

But in the end there may well no be a right or wrong decision and each of us must balance up what we think is the best for the vehicle and our safety as well as longevity and cost. Sadly the insurers may well take an opposing view so it may be best to follow the manufacturer's guidelines.


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## 747 (Oct 2, 2009)

Dave, I have seen lots of comments about strengthened sidewalls on CP tyres due to motorhomes standing for long periods, especially over Winter. In cold weather the tyre pressure will also drop slightly. That is why my tyres overwinter with extra pressure if I know the motorhome will not be used. 10 minutes with a tyre inflator stiffens the sidewalls no end. :grin2:


Some owners also have a phobia about 'flat spots' yet I have never heard of anyone complaining that a tyre has been ruined by this.


As you say, we all have our own take on these matters and as long as we are happy .... who cares. :wink2:


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## Pudsey_Bear (Sep 25, 2008)

We did have flat spots one one van Jim a few years ago, Appalling to drive, but after a good run they seemed to settle down, I ended up selling the van a few months later with the same tyres on, test drive it drove spot on.


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## coppo (May 27, 2009)

Just normal tyres for me with the correct load rating, I know someone who says the Continental 4 season 120 load rated tyres make the CP tyres look like dinky toy ones, when you look at the structure of the sidewalls.


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## pete4x4 (Dec 20, 2006)

Dont wish to prolong this thread any longer but in reply to insurance validity, this is not considered a modification and straight from Comfort Insurance and I quote: "From an insurance point of view, we advise that the Motorhome, including the tyres, must remain road legal at all times." 



There is no legal requirement to fit CP tyres just a recommendation and I also have Michelin saying they are "safe to use" so I'm happy and hopefully looking forward to not getting stuck on grass as much


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## Penquin (Oct 15, 2007)

As I said;_ "Each person must make up their own mind as to what they wish to use."_.

I stand by that and will accept that people's views will differ, thank heavens, as that is how things will progress and conclusions can be drawn as to which is the best to use.

If everyone was compelled to use the same then progress would not be made and we would still have a man with a red flag walking in front of us.....


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## aldra (Jul 2, 2009)

We have the tyres recommended when we upgraded our van to 3850 

I haven’t a clue if they are the best

I leave that to Albert

I’m not sure he has a clue either 

Sandra


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