Chelston Motorhomes

[Derek Uzzell]

TheEscapist - 2019-04-28 9:20 AM

 

Hello Derek

 

Thanks.

 

The TyrePal model is TYC2158 and it's new with the van.

 

The problem with running at 80 psi is that it will mean the pressures rise significantly over the max on the van of 83 psi when at running temperature or are you suggesting running at 80 psi when 'hot' which would mean around 70 at 'cold'?

 

Paul

 

I’m suggesting that you refer to the “COLD TYRE INFLATION PRESSURE” page of your Fiat Ducato Owner Handbook that, for 225/75 R16 CP “Camping tyres” will advise a 5.5bar COLD pressure for front and rear axles or, if the tyres have a 118 load index and the motorhome has a 4400kg chassis, 5.5bar (front) and 6.0bar (rear).

[Robinhood]

Derek Uzzell - 2019-04-28 10:51 AM

 

I’m suggesting that you refer to the “COLD TYRE INFLATION PRESSURE” page of your Fiat Ducato Owner Handbook that, for 225/75 R16 CP “Camping tyres” will advise a 5.5bar COLD pressure for front and rear axles or, if the tyres have a 118 load index and the motorhome has a 4400kg chassis, 5.5bar (front) and 6.0bar (rear).

 

....funnily enough, those aren't the pressures quoted in my manual, BUT, the OP states that he doesn't have "Camping" tyres anyway, but Continental Vanco Four Seasons 2.

 

I would advise the OP to check the pressures in the manual (and also possibly to ensure that he's using an appropriate version of the manual by downloading from

 

http://aftersales.fiat.com/elum/Home.aspx?brand_code=77&id_language=2

 

...using the VIN number.

 

FWIW, the June 2018 edition of the manual has the attached entries for tyre pressures, which shows 5.2 bar all round for (non-camping) M+S tyres (complicated by another value for 4400kg GVW vehicles which might or might not be seen as taking precedence :-( ).

 

For the OP's peace of mind, it also indicates that the pressures might increase by up to 1Bar in use, from the quoted cold values.

 

[Solwaybuggier]

They may have changed since ours was produced in 2015, but our Carthago manufacturer’s handbook gives recommended tyre pressures dependent on axle weights. (For what it’s worth, at our axle weights that came out at 45 psi front, 60 rear, but obviously yours is a much heavier van, even before your added spec.) This may also date back to the time when Michelin would give you a recommended pressure if you gave them weighbridge figures, rather than a blanket 80 psi, which in my experience on a lighter van is liable to shake you to bits.

[TheEscapist]

Fiat manual says 75 psi.

 

Carthago manual says maximum of 70 psi by axle weight.

 

Sticker in fuel cap says maximum of 65 psi by axle weight.

 

Need to ask Chelston to weigh the axles.

[Derek Uzzell]

I’d missed that Paul’s Carthago motorhome had “Four Seasons” tyres.

 

The Four Seasons 225/75 R16 size seems to be advertised with a load index of 121 (which would make it a 10ply-rating (10PR) tyre) and Continental’s handbook indicates that it will handle a maximum single-fitment-axle loading of 2900kg at an inflation-pressure of 5.75bar (83.4psi). A 75psi (5.17bar) pressure would relate to an axle-loading of about 2650kg.

 

Inflation-pressure advice is always based on ‘cold' tyres, which means when the vehicle has not recently been driven and (if I remember correctly what a Continental technician once told me when I asked what ‘cold’ meant) at an industry standard ‘out-of-the-sun’ ambient temperature of 20 degrees Centigrade.

 

Even at a 75psi pressure the while-driving pressure may (as Robinhood mentioned) rise significantly and approach 90psi. So if the 75psi pressure is appropriate for Paul’s motorhome’s axle-loadings and the TyrePal system is producing alarms because the TyrePal monitor’s ‘high pressure’ value for the Carthago’s rear tyres is being exceeded, that value will need to be increased.

 

I run my Rapido’s rear tyres at a 5.0bar (72psi) cold-tyre pressure. Driving in hot weather will cause that pressure to rise into the upper 80s psi, so I’ve set my TyrePal monitor’s ‘high pressure’ value to 90psi.

[TheEscapist]

Thanks Derek. Very helpful....

[Derek Uzzell]

I think the TyrePal product you have is a TC215B as shown on this User Manual file

 

https://www.tyrepal.co.uk/wp-content/uploads/2017/06/TC215B-user-manual-contents-20160222.pdf

 

The manual provides the following advice about setting the system’s ‘alert levels'

 

4.4 Set units of pressure and alert levels

 

Pressure units can be set to display in psi or bar, and temperature in °C or °F. Pressure alerts are set individually for each of the three axles on the towing vehicle (tractor) while the trailer settings apply to all axles on the trailer. We recommend that the high pressure alert is set at 20% above the manufacturer’s recommended pressure, and the low alert 15% below. The temperature alert level applies to all tyres. The factory set default is 70°C and we recommend that this is not changed.

 

So if a tyre were inflated to 75psi, the advice would result in the high-pressure alert being set to 90psi and the low-pressure alert to 64psi.

 

It would be wise (as you are planning to do) to get ‘weighed’ axle loadings for your Carthago to confirm that the 75psi pressure is adequate for its ’normal usage’ axle loading. If it is and the TyrePal system’s high-pressure alert for the rear-axle is currently set to 90psi and that alert is being triggered, I suggest you increase that value to 95psi and (assuming this action stops the high-pressure alert happening while driving) use the system to monitor the pressure that the rear tyres actually rise to.

 

Although the high-pressure alert can indicate that a tyre is overheating because its inflation pressure is insufficient for the load that is supporting, it’s the low-pressure alert that will show that there’s an air-loss problem (slow puncture, tyre-valve leakage, etc.)

 

If the ‘weather based’ pressure change in a motorhome tyre is factored in, it may be necessary to set the high-pressure alert above 20%. For example, if your Carthago’s rear tyres are inflated to 75psi now in the UK and you next take the vehicle to a country where the weather is a lot hotter than here, that 75psi pressure might have increased naturally to (say) 80spsi. And if the TyrePal system’s rear-tyre high-pressure alert were set to 90psi, driving the Carhago in the hot country could easily result in the alert occurring.

[Keith T]

In response to your original enquiry I have been with Chelston as a customer for 12 years or so, and have bought two motorhomes from them....Having been an owner of such vehicles from various dealers for 25 years or so, I have always put everything in writing, and always maintained an excellent relationship both with the sales people and after sale/warranty.

Both vehicles - one a Burstner the other Autotrail - have not been without their problems and issues, as indeed have previous Autosleepers and Rapido models....but always I have received extremely courteous service and contact, and as mentioned as well as talking through the issues at the time, have always updated by email

Turning to your point about who deals with what, I have never expected the salesperson to be the contact point for aftersales matters, and have always had a point of contact via the warranty .section...…

…...you comment re the change of person through whom you have contact, and I suggest that from time to time any companies may well modify its route for dealing with customers, and so long as you have this there should be no problems in maintaining this contact...subject to any staff and management changes within the company....

I have found it very important to establish and maintain a good working relationship which has to work both ways, and fortunately have always managed to have this.

[TheEscapist]

I have a problem now with the van which is stopping me taking delivery.

 

The van is at the dealer and apparently all other matters have been resolved but I'm n ot convinced the tyre problem has.

 

On the advice of members here, I asked Chelston to weigh the van axles separately.

 

The results are:

 

Front: 1,860 kgs

Rear: 2,900 kgs

 

Total: 4,760 kgs

 

Van total weight allowance is 4,800 kgs.

 

This is with full fresh water tank but no luggage, food and drink etc. so I can manage if I carry less water, even though its close to the limit.

 

The issue is with the tyre pressures. The TyrePal system warnings when tyres got hot drew me to check the recommended cold tyre pressures.

 

information from Fiat, Continental and Carthago differs but I defer to the plate inside the filler cap as it should be the most specific.

 

I attach the image here and the tyres fitted are the bottom line 225 C tyres as stated.

 

This to me appears to show they can't handle the rear axle weight but the CP tyres could.

 

Chelston Motorhomes tell me they have spoken to Carthago and Continental in Germany and it's all fine and they recommend 80 psi all round.

 

This doesn't make sense to me hence I'm asking advice here. The filler cap table appears to tell me 50 psi (3.5 bar) front and rear overloaded but with the CP tyre 50 psi front and 65 psi rear.

 

This is very different information.

 

What should I do here? I have made it clear to Chelston I'm not taking delivery until I'm happy it's safe to drive. They fitted all the extras and know the vehicle as they sell Carthago. They are saying it's all fine at 80 psi, don't worry.

 

I have also written directly to Carthago to say I am not happy to take delivery of their manufactured vehicle and they should support the dealer to advise the solution.

 

Thanks

 

Paul

[TheEscapist]

TheEscapist - 2019-05-03 1:21 PM

 

I have a problem now with the van which is stopping me taking delivery.

 

The van is at the dealer and apparently all other matters have been resolved but I'm n ot convinced the tyre problem has.

 

On the advice of members here, I asked Chelston to weigh the van axles separately.

 

The results are:

 

Front: 1,860 kgs

Rear: 2,900 kgs

 

Total: 4,760 kgs

 

Van total weight allowance is 4,800 kgs.

 

This is with full fresh water tank but no luggage, food and drink etc. so I can manage if I carry less water, even though its close to the limit.

 

The issue is with the tyre pressures. The TyrePal system warnings when tyres got hot drew me to check the recommended cold tyre pressures.

 

information from Fiat, Continental and Carthago differs but I defer to the plate inside the filler cap as it should be the most specific.

 

I attach the image here and the tyres fitted are the bottom line 225 C tyres as stated.

 

This to me appears to show they can't handle the rear axle weight but the CP tyres could.

 

Chelston Motorhomes tell me they have spoken to Carthago and Continental in Germany and it's all fine and they recommend 80 psi all round.

 

This doesn't make sense to me hence I'm asking advice here. The filler cap table appears to tell me 50 psi (3.5 bar) front and rear overloaded but with the CP tyre 50 psi front and 65 psi rear.

 

This is very different information.

 

What should I do here? I have made it clear to Chelston I'm not taking delivery until I'm happy it's safe to drive. They fitted all the extras and know the vehicle as they sell Carthago. They are saying it's all fine at 80 psi, don't worry.

 

I have also written directly to Carthago to say I am not happy to take delivery of their manufactured vehicle and they should support the dealer to advise the solution.

 

Thanks

 

Paul

 

Is the solution a specialised camper tyre such as this?

 

https://blobs.continental-tires.com/www8/servlet/blob/2469786/793f9294f46eac38e1b5781ba502f9e7/download-pfs-vancontact-camper-data.pdf

 

Does anyone else use this tyre?

 

Thanks

 

Paul

[TheEscapist]

TheEscapist - 2019-05-03 2:32 PM

 

TheEscapist - 2019-05-03 1:21 PM

 

I have a problem now with the van which is stopping me taking delivery.

 

The van is at the dealer and apparently all other matters have been resolved but I'm n ot convinced the tyre problem has.

 

On the advice of members here, I asked Chelston to weigh the van axles separately.

 

The results are:

 

Front: 1,860 kgs

Rear: 2,900 kgs

 

Total: 4,760 kgs

 

Van total weight allowance is 4,800 kgs.

 

This is with full fresh water tank but no luggage, food and drink etc. so I can manage if I carry less water, even though its close to the limit.

 

The issue is with the tyre pressures. The TyrePal system warnings when tyres got hot drew me to check the recommended cold tyre pressures.

 

information from Fiat, Continental and Carthago differs but I defer to the plate inside the filler cap as it should be the most specific.

 

I attach the image here and the tyres fitted are the bottom line 225 C tyres as stated.

 

This to me appears to show they can't handle the rear axle weight but the CP tyres could.

 

Chelston Motorhomes tell me they have spoken to Carthago and Continental in Germany and it's all fine and they recommend 80 psi all round.

 

This doesn't make sense to me hence I'm asking advice here. The filler cap table appears to tell me 50 psi (3.5 bar) front and rear overloaded but with the CP tyre 50 psi front and 65 psi rear.

 

This is very different information.

 

What should I do here? I have made it clear to Chelston I'm not taking delivery until I'm happy it's safe to drive. They fitted all the extras and know the vehicle as they sell Carthago. They are saying it's all fine at 80 psi, don't worry.

 

I have also written directly to Carthago to say I am not happy to take delivery of their manufactured vehicle and they should support the dealer to advise the solution.

 

Thanks

 

Paul

 

Is the solution a specialised camper tyre such as this?

 

https://blobs.continental-tires.com/www8/servlet/blob/2469786/793f9294f46eac38e1b5781ba502f9e7/download-pfs-vancontact-camper-data.pdf

 

Does anyone else use this tyre?

 

Thanks

 

Paul

 

Maybe the easier way to resolve this is to realise that the tyres on my van aren't the best or latest models and replace them.

 

In which case, what are the latest and best tyres for a motorhome with my axle weights, especially a high rear axle weight?

[Wasnt Me]

TheEscapist - 2019-05-03 12:21 PM

 

I have a problem now with the van which is stopping me taking delivery.

 

The van is at the dealer and apparently all other matters have been resolved but I'm n ot convinced the tyre problem has.

 

On the advice of members here, I asked Chelston to weigh the van axles separately.

 

The results are:

 

Front: 1,860 kgs

Rear: 2,900 kgs

 

Total: 4,760 kgs

 

Van total weight allowance is 4,800 kgs.

 

This is with full fresh water tank but no luggage, food and drink etc. so I can manage if I carry less water, even though its close to the limit.

 

The issue is with the tyre pressures. The TyrePal system warnings when tyres got hot drew me to check the recommended cold tyre pressures.

 

information from Fiat, Continental and Carthago differs but I defer to the plate inside the filler cap as it should be the most specific.

 

I attach the image here and the tyres fitted are the bottom line 225 C tyres as stated.

 

This to me appears to show they can't handle the rear axle weight but the CP tyres could.

 

Chelston Motorhomes tell me they have spoken to Carthago and Continental in Germany and it's all fine and they recommend 80 psi all round.

 

This doesn't make sense to me hence I'm asking advice here. The filler cap table appears to tell me 50 psi (3.5 bar) front and rear overloaded but with the CP tyre 50 psi front and 65 psi rear.

 

This is very different information.

 

What should I do here? I have made it clear to Chelston I'm not taking delivery until I'm happy it's safe to drive. They fitted all the extras and know the vehicle as they sell Carthago. They are saying it's all fine at 80 psi, don't worry.

 

I have also written directly to Carthago to say I am not happy to take delivery of their manufactured vehicle and they should support the dealer to advise the solution.

 

Thanks

 

Paul

 

I know this is not what you are asking and I am sorry if it's not helpful.

 

Are you sure you can manage with that payload? That doesn't seem very much, what capacity is the water tank?

 

From what I can see the vehicle is not useable with the payload described? Have you factored the weight of passengers?

[Derek Uzzell]

Paul

 

You said earlier in this discussion that the tyres fitted to your Carthago motorhome are

 

Continental VancoFourSeason 2

Size 225/75 R16 C

 

In my subsequent posting of 28 April 2019 3:02 PM I commented

 

The Four Seasons 225/75 R16 size seems to be advertised with a load index of 121 (which would make it a 10ply-rating (10PR) tyre) and Continental’s handbook indicates that it will handle a maximum single-fitment-axle loading of 2900kg at an inflation-pressure of 5.75bar (83.4psi). A 75psi (5.17bar) pressure would relate to an axle-loading of about 2650kg.

 

A sample advert is here

 

https://www.mytyres.co.uk/rshop/Tyres/Continental/VancoFourSeason-2/225-75-R16C-121-120R-10PR/R-148178

 

and you’ll see that the tyre’s ‘full definition’ is

 

Continental VancoFourSeason 2 225/75 R16C 121/120R

 

An explanation of load index (121/120) and speed rating ® is provided here

 

https://www.tyresizecalculator.com/tyres/tire-speed-rating-and-load-index-for-the-light-truck-tires

 

An “R” speed symbol indicates a speed of 170kmh/106mph - so you don’t really need be concerned about that.

 

As your Carthago’s rear-axle type is ’single fitment’ (ie. there is a single wheel on each end of the axle) the load index of 121 will apply. A load index of 121 indicates that a tyre has a load-carrying capability of 1450kg that in your Carthago’s case, equates to a maximum rear-axle loading of 2900kg (2 x 1450kg).

 

2900kg is the rear-axle 'measured weight’ you’ve just provided, so the present Continental VancoFourSeason 2 tyres are technically capable of supporting that load at (according to Continental’s technical chart) an inflation-pressure of 5.75bar/83.4psi). As you won’t be reaching the 106mph speed rating, inflating the rear tyres to 80psi (as you’ve been advised) should be OK.

 

For a measured weight of 1860kg Continental’s chart suggests an inflation-pressure of around 3.3bar/48psi but I suggest you choose at least 4.0bar/58psi (2170kg load) to cope better with braking/cornering stresses and because your Carthago is front-wheel drive. You could use 80psi but the ride might prove harsh.

 

The appropriate Continental VanContact Camper tyre has a specification of 225/75 R16 CP 118R with the 118 load index indicating a single-fitment axle maximum loading of 2640kg - hence unsuitable for your motorhome’s 2900kg rear-axle load. Basically, unless a larger size of tyre were fitted that had a load index above 121, the tyres currently on your Carthago are the best you can get.

 

(With a fresh-water capacity of 235 litres, you should be able to usefully reduce the rear-axle weight by travelling with a part-filled tank.)

 

[TheEscapist]

TheEscapist - 2019-05-03 2:55 PM

 

TheEscapist - 2019-05-03 2:32 PM

 

TheEscapist - 2019-05-03 1:21 PM

 

I have a problem now with the van which is stopping me taking delivery.

 

The van is at the dealer and apparently all other matters have been resolved but I'm n ot convinced the tyre problem has.

 

On the advice of members here, I asked Chelston to weigh the van axles separately.

 

The results are:

 

Front: 1,860 kgs

Rear: 2,900 kgs

 

Total: 4,760 kgs

 

Van total weight allowance is 4,800 kgs.

 

This is with full fresh water tank but no luggage, food and drink etc. so I can manage if I carry less water, even though its close to the limit.

 

The issue is with the tyre pressures. The TyrePal system warnings when tyres got hot drew me to check the recommended cold tyre pressures.

 

information from Fiat, Continental and Carthago differs but I defer to the plate inside the filler cap as it should be the most specific.

 

I attach the image here and the tyres fitted are the bottom line 225 C tyres as stated.

 

This to me appears to show they can't handle the rear axle weight but the CP tyres could.

 

Chelston Motorhomes tell me they have spoken to Carthago and Continental in Germany and it's all fine and they recommend 80 psi all round.

 

This doesn't make sense to me hence I'm asking advice here. The filler cap table appears to tell me 50 psi (3.5 bar) front and rear overloaded but with the CP tyre 50 psi front and 65 psi rear.

 

This is very different information.

 

What should I do here? I have made it clear to Chelston I'm not taking delivery until I'm happy it's safe to drive. They fitted all the extras and know the vehicle as they sell Carthago. They are saying it's all fine at 80 psi, don't worry.

 

I have also written directly to Carthago to say I am not happy to take delivery of their manufactured vehicle and they should support the dealer to advise the solution.

 

Thanks

 

Paul

 

Is the solution a specialised camper tyre such as this?

 

https://blobs.continental-tires.com/www8/servlet/blob/2469786/793f9294f46eac38e1b5781ba502f9e7/download-pfs-vancontact-camper-data.pdf

 

Does anyone else use this tyre?

 

Thanks

 

Paul

 

Maybe the easier way to resolve this is to realise that the tyres on my van aren't the best or latest models and replace them.

 

In which case, what are the latest and best tyres for a motorhome with my axle weights, especially a high rear axle weight?

 

I'm also being told I need camper tyres on the motorhome not van tyres as supplied by Carthago, for insurance reasons. Seems the vehicle isn't even legal to drive?

[TheEscapist]

Hello Derek

 

Yes, I'm in full agreement with ll you have said.

 

However, my concerns are:

 

a. the tyre fitted is a commercial tyre not a motorhome tyre. Is that ok for insurance purposes?

 

b. Carthago quote a CP tyre in the filler cap but no-one has heard of such a tyre!

 

c. I have no margin for error with weight. Yes, I can drain tanks but I'm still on the limit once I add some luggage and food etc, albeit I can store most of this forward.

 

Cheers

 

Paul

 

[monique.hubrechtsgm]

CP tyre is a camping tyre. every one in camping is aware off that. It appears this is not realistic Actual weight according MAM.

[Billggski]

As the sticker and, presumably, the handbook, state that "C" tyres are a standard fitment, there should be no problem with insurance.

Are you sure Chelston actually weighed the axles? The figures look suspiciously like the max load from the specification sheet, giving you no payload at all!

[Derek Uzzell]

The “CP” marking on a tyre does not indicate that it has been tested and met any defined technical criteria.

 

“CP” (“Camping Pneu”) merely indicates that the tyre’s manufacturer is marketing that tyre as being particularly suitable for use on recreational vehicles (motorhomes). The only ’technical’ element of the “CP” marking is that - for some unfathomable reason- the ETRTO (European Tyre and Rim Technical Organization) that oversees tyre-marking standards only permits the “CP” marking to be used on tyres that are 8-ply-rated (8PR). Ply-rating does not relate directly to how a tyre is constructed: it’s just an out-of-date (but convenient) way of indicating a tyre’s load-carrying capablility (USA explanation here)

 

https://www.sttc.com/resources/tire-info/ply-rating/

 

and a tyre’s load-index provides a much more accurate datum. What the ETRTO’s stipulation does mean though is that any tyre that could be admirably suitable for a motorhome, but has a load-carrying capability that exceeds the 8PR category (eg, your 10PR Continental VancoFourSeason 2 tyres) is unable to bear the “CP” marking.

 

There’s no legal demand that a motorhome must have “CP”-marked tyres and many (most?) panel-van conversions don’t have them. They tend to be fitted as original equipment to coachbuilt motorhomes that are Citroen/Fiat/Peugeot based and my 2005 Ford-based coachbuilt Hobby had the “C”-marked tyres normally fitted to Ford Transit commercial vehicles.

 

As there’s no legal imperative for your Carthago to have “CP”-marked tyres, there can be no potential insurance-related problems due to it not having them. Besides which, if your motohome has a maximum authorised rear-axle loading of 2900kg, there’s no 225/75 R16 tyre that is “CP”-marked that could handle that loading.

 

The important issue is not the currently-fitted high-strength tyres, but a) ensuring that the Carthago’s overall and axle weights do not exceed their authorised maxima and b) once all the ‘adjustable’ stuff (water, luggage, food, etc.) has been taken onboard, that the inflation-pressures for the vehicle’s front and rear tyres are appropriate for the resultant axle loadings when the Carthago is in 'normal travelling condition’.

[colin]

A couple of things.

From what I can gather you have purchased the the 4.9t version of this van, this has quite a reduced MAM compared to the rest.

You have had extras fitted.

You have had it weighed with 225litre of water on board but little else and this has shown the rear axle to be at it's maximum for 121load index tyres.

You haven't posted what the vehicle data plate shows for axle maximums, I suspect the rear to be 2.9t.

You could as Derek posted reduce water but this will still give little extra, what ever you put in the van (including yourself and passengers) will put extra load on rear axle no matter how far forward you put it as it's impossible to put any payload in front of front axle.

 

 

[colin]

I've just been looking at CP tyres of the size fitted to your van, they have a lower load index which means they should not be used at the axle load you have at rear.

Sorry I see Derek has already pointed this out.

I wonder if the data plate on tyre pressure at 3400kg is actually for a twin axle even if it says single tyres.

[monique.hubrechtsgm]

Yes i think Paul has a problem. However the scala of the carthago liner for two has it all. Fiat-AL-Ko single rear axle or two. Or Iveco chassis. versions. The MIRO AND MAM are to close.Tyres load index should just fit the wheel. But they have a margin. And do not forget the wheel material itself. I saw some dealers who offer the type of paul whit alko 4c air suspension. Weight up grade?

[Derek Uzzell]

colin - 2019-05-03 6:02 PM

 

...I wonder if the data plate on tyre pressure at 3400kg is actually for a twin axle even if it says single tyres.

 

I think the answer is simply that the 3400kg figure is wrong!

 

I’ve looked at the 2017-2018 Continental Technical Databook and the pressure-to-axle-weight values for a 225/75 R16 tyre (“C” or “CP” marked) tally with the figures on the data-plate except for an occasional 5kg variation EXCEPT for the 4.5bar figure for the 225/75 R16 CP tyre. This reads 3400kg on the Carthago data-plate, but (for a 4.5bar pressure for that tyre specification) is stated as 2395kg on the Continental listing. 2395kg is 5kg short or 2400kg - draw your own conclusion...

[TheEscapist]

Billggski - 2019-05-03 5:23 PM

 

As the sticker and, presumably, the handbook, state that "C" tyres are a standard fitment, there should be no problem with insurance.

Are you sure Chelston actually weighed the axles? The figures look suspiciously like the max load from the specification sheet, giving you no payload at all!

 

I have the certificates now from the weighbbridge and it is as stated.

[TheEscapist]

Derek Uzzell - 2019-05-03 5:30 PM

 

The “CP” marking on a tyre does not indicate that it has been tested and met any defined technical criteria.

 

“CP” (“Camping Pneu”) merely indicates that the tyre’s manufacturer is marketing that tyre as being particularly suitable for use on recreational vehicles (motorhomes). The only ’technical’ element of the “CP” marking is that - for some unfathomable reason- the ETRTO (European Tyre and Rim Technical Organization) that oversees tyre-marking standards only permits the “CP” marking to be used on tyres that are 8-ply-rated (8PR). Ply-rating does not relate directly to how a tyre is constructed: it’s just an out-of-date (but convenient) way of indicating a tyre’s load-carrying capablility (USA explanation here)

 

https://www.sttc.com/resources/tire-info/ply-rating/

 

and a tyre’s load-index provides a much more accurate datum. What the ETRTO’s stipulation does mean though is that any tyre that could be admirably suitable for a motorhome, but has a load-carrying capability that exceeds the 8PR category (eg, your 10PR Continental VancoFourSeason 2 tyres) is unable to bear the “CP” marking.

 

There’s no legal demand that a motorhome must have “CP”-marked tyres and many (most?) panel-van conversions don’t have them. They tend to be fitted as original equipment to coachbuilt motorhomes that are Citroen/Fiat/Peugeot based and my 2005 Ford-based coachbuilt Hobby had the “C”-marked tyres normally fitted to Ford Transit commercial vehicles.

 

As there’s no legal imperative for your Carthago to have “CP”-marked tyres, there can be no potential insurance-related problems due to it not having them. Besides which, if your motohome has a maximum authorised rear-axle loading of 2900kg, there’s no 225/75 R16 tyre that is “CP”-marked that could handle that loading.

 

The important issue is not the currently-fitted high-strength tyres, but a) ensuring that the Carthago’s overall and axle weights do not exceed their authorised maxima and b) once all the ‘adjustable’ stuff (water, luggage, food, etc.) has been taken onboard, that the inflation-pressures for the vehicle’s front and rear tyres are appropriate for the resultant axle loadings when the Carthago is in 'normal travelling condition’.

 

Trying to find out the maximum axle loads now. I am sure Chelston know and have had this discussion as they have been talking to Carthago all week. Seems to me there is some economy with the truth or at least not volunteering the whole situation! Getting weary of all this!

[monique.hubrechtsgm]

Paul has an interface fiat- Alko chassis. My Partner can bolt on alko/VB Air suspension which is the same in two days whit two persons. It is just a lego kit.. Including fiat/Iveco can - bus software. Do not worry we are standby to help.