# Tyre Pressures - A reply from Continental Automobil



## UncleNorm

Hello dear Friends...

I promised a new thread...

Last Sunday, I emailed Continental Tyres to ask what my tyre pressures should be. I offered the relevant tyre details... Fiat Ducato, X2/50, tyres information: 215/70 R 15 CP 109R

I included my axle weights which resulted from my last visit to a weighbridge... Yes, I do take my own advice! 8O

Rear axle 1900kg (max 2000)
Front axle 1540kg (max 1850)
Gross 3440 kg (max 3500)

The following is the reply from Craig, the Product Support Engineer of Continental Automobil. He has consented to having his reply published on MHF:

_*The pressures you require are as follows:

Front: 3.25bar - 47psi pressure applicable to a maximum permissible load of1590kg. 1850kg Max loading at 4bar - 58psi (1875kg maximum at this pressure)

Rear: 4.25bar - 61psi pressure applicable to a maximum permissible load of1970kg. 2000kg Max loading at 4.5bar - 65psi (2060kg maximum at this pressure)

As a general rule for pressures on this tyre, every 100kg added from the base figure of 1490kg at 3bar (43.5psi) will require an increase of 0.25bar(3.6psi) in pressure up to a maximum of 2060kg at 4.5bar (65psi)

We do get a substantial amount of queries regarding pressures. Unfortunately, there is a distinct lack of understanding on the subject which isn't helped by the apparent reluctance of coach-builders to specify the pressures required. Naturally, all pressures are dependent on load so providing any queries received contain the information requested, we can advise accordingly. I've helped a few other organisers of motorhome/camping clubs and associations in the past so we are all working to educating the consumers as to what is required. Hopefully this will provide a greater understanding for them. *_

Now those pressures of 47 and 61 psi are FAR removed from what is on MY Fiat door pillar, which says 72.3 and 79.5!! What a difference!!  Even Continental's MAXIMUM pressures of 58 and 65 psi are far removed from those quoted by Fiat!!

So, in a nut-shell... don't go by the figures on the label... visit a weighbridge (£5) and note the actual axle weights... then contact the TYRE manufacturer for the relevant pressures! Couldn't be simpler!! :roll: :wink:

I also asked Craig about tyre ageing... He replied thus:

_*Age cracking is indeed an issue. In some instances, it is superficial but it is always recommended that the tyres are thoroughly checked before being put back into service. I have examined many tyres that have substantial cracking issues to the tread area and sidewalls. Naturally, continued use when they are affected to such a degree exacerbates the condition. Rubber, being a natural compound, will age over time. There are inhibitors that are added to the tyre compound to help prevent this condition occurring, but the nature of the vehicle application means that they suffer most when left static (particularly under load) for prolonged periods. It does help to cover them to protect them from ultraviolet rays when not in use - providing the vehicles are stored outdoors of course.*_

So, I have MY answers regarding tyre pressures. Craig has also clarified some issues regarding tyre ageing... But the replies also show one company's readiness to help its customers and families to remain safe when travelling in their motorhomes.

I propose a vote of thanks to Craig and Continental Automobil for their prompt and informative replies. Just what we needed at MHF!


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## greygit

Thanks for the post Unclenorm very enlightening , I will have to get to a weigh bridge and check our weights.
Gary


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## oilslick

*Interesting....*

This is very interesting.

I fully agree with the idea of ignoring the sticker. If I were to use the pressures advised on our sticker we would actually be exceding the max pressure rating marked on they tyre! (original supplied tyres too). I noticed this a couple of days ago and felt a little confused / amazed but it didnt really sink in properly until reading this thread.

I wonder whether any accidents have been caused because of loss of grip due to this misleading information?

It would appear that the sticker is a standard fittment for the Fiat van and the tyres that it is suplied with?

I am surprised that the converters have not cottoned on to this and produced their own sticker.

I will be calculating the correct pressures for my tyres.

One question norm... are your continentals the camping ones?

Grant


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## steco1958

Its fairly obvious that this sticker should be ignored, as it is the original information from the manufacture of the base vehicle, on different tyres, with a different load bearing.

I have a document from "Tyre Safe" but it is 2.7Mb so not able to post, if anyone can assist I think it would be a useful resource.

Steve


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## steco1958

Addendum,

I have just been given the link Cheers Cronkle

Here it is:-

http://www.tyresafe.org/data/files/motorhome 08.pdf


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## UncleNorm

Yes Grant, my Continentals are VancoCamper 

215/70 R 15 CP 109R DOT 1707 . :wink:


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## bognormike

Thanks Unclenorm for the info & steco for posting that link. I do remember seeing that before, and it's worthwhile printing off the PDF and keeping it in the 'van for reference.


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## Steamdrivenandy

Good morning UN, or should I say Big Brother Adria  

The Compact has the same tyres and tyre pressure sticker as your big boy.

Your post prompted me to look out my last weighbridge ticket from March '09. The Compact weighed 1400kg front, 1300kg rear, overall 2700kg Gross. That ties in nicely with Adria's MIRO of 2590kg

If all the tanks were empty at the time of weighing then full fresh, waste and diesel would add around 320kg max. making the Gross 2900kg and then there's a few kgs for other kit. I reckon we probably run around at about 3000kg normally. That's an enormous 500kg spare payload.

I reckon that would be split 1450kg front/1550kg rear, which by Craig's figures suggests the fronts should be at the minimum 3 bar (43.5) and the rears at 3.25 bar (47). As you say it's a helluva difference from 72 and 80 on the door post.

Have you reduced your pressures and have you noticed any difference in handling, ride, mpg etc?

Andy


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## steco1958

Unfortunatley, the pdf from Tyre safe does not include my tyre size.

225 / 75 / R 16 CP, with a load index of 116Q.

I have contacted Michelin Tech Services who have given me pressures of 65psi(Front) and 80psi(Rear), based on the max load for Axle weights.

Steve


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## Wizzo

steco1958 said:


> I have contacted Michelin Tech Services who have given me pressures of 65psi(Front) and 80psi(Rear), based on the max load for Axle weights.
> Steve


IIRC Michelin do not supply exact tyre pressures for given axle weights any longer. I would say that they have just given you what they consider a maximim pressure. If you take the nearest size in the TyreSafe booklet which is 225/65/16 I believe you will get a better idea of what the pressures ought to be. Looking at the chart, the bigger the tyre in volume and the higher the load index then the lower the pressure required for a given weight. Therefore if anything the 215/65's pressures will if anything be higher than you need.

JohnW


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## steco1958

So are you saying that I should be running at 62psi front and and 69psi rear.

Steve


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## Wizzo

steco1958 said:


> So are you saying that I should be running at 62psi front and and 69psi rear.
> Steve


If that's what the chart equates 225/65/16's to your axle loads then yes that is what I am saying. It has been said in the not too distant past on here that Michelin no longer quote actual pressures for given size/weight equations. They seem to have taken to covering their backs along with a lot of others in this day and age. In the toss up between giving out pressures that are too high and ones that are too low then the first option is the lesser of two evils.

However, I would not like to be driving my van in the wet with 80psi in the tyres and then expect it to stop like it should. Although it may be the lesser evil, in my book it's still wrong.

JohnW


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## HikerG

Interesting topic and only makes me more confused! My Hymer B564 manual contains recommended tyre pressure ratings in BAR that when I convert to PSI come out to 73 PSI. 

Now I appreciate that it's hard to know what brand of tyre was originally fitted but I cannot understand why there would be such a difference between this and the advice given by the tyre manufacturer. 

So does a tyre have a recommended pressure regardless of the vehicle it's fitted to? Are we saying that we should inflate to the same PSI regardless of whether the tyre is being fitted to a van or a motorhome?

I plan to go over a weighbridge soon just to check how close to my maximum weight I am but now I'm left wondering what tyre pressure to use!


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## Steamdrivenandy

HikerG said:


> Interesting topic and only makes me more confused! My Hymer B564 manual contains recommended tyre pressure ratings in BAR that when I convert to PSI come out to 73 PSI.
> 
> Now I appreciate that it's hard to know what brand of tyre was originally fitted but I cannot understand why there would be such a difference between this and the advice given by the tyre manufacturer.
> 
> So does a tyre have a recommended pressure regardless of the vehicle it's fitted to? Are we saying that we should inflate to the same PSI regardless of whether the tyre is being fitted to a van or a motorhome?
> 
> I plan to go over a weighbridge soon just to check how close to my maximum weight I am but now I'm left wondering what tyre pressure to use!


It may be that the motorhome converter has researched the issue and the figures in their manual are their considered recommendations. On the other hand they may just be quoting the chassis manufacturers figure from the plate/sticker that's on there somewhere and that figure will be based on the maximum load their chassis can carry.

Now some motorhomes may spend their whole life loaded to the max., in which case the manual figures could be OK.

On the other hand my van has a max weight of 3500kg and with nothing on board it weighs approx. 2600kg, giving a 900kg payload.
I reckon that we usually run it at somewhere around 3000kg, so 500kg under the max. weight, which is an awful lot. I wouldn't be at all surprised that to some extent it's affecting handling and braking, especially in the wet, and leading to faster tyre wear and reduced crew comfort.

It's on Continental Camper Tyres and Conti have told Norm what they consider to be the optimum pressure for their tyres, depending on the load on each axle.

I think I'm happier following the tyre makers recommendation, rather than a catch all figure for the maximum my chassis can legally carry.

Andy


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## suedew

A well timed post, thought my rear tyres looked a little soft this morning, had look at the door pillar, 'please contact tyre manufacturer for correct pressure'. 
Now have all the relevant information to get it right I hope.
have bookmarked this post for future reference.
Thanks Norm et al
Sue


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## oilslick

*Any comments?*

Are there any more comments on people trying these lower pressures?

Swift quote the "base vehicle" in their literature, which as quoted before is far higher than continental quote. (Continental have got to be right about THEIR tyres! What do you say Swift guys?

I am going to try Continentals figures, but dropping the fronts so much seems a little nervy!

Grant


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## nicholsong

After reading comment that Michelin will not give precise info, I re read their e-mail sent to them in response to mine giving axle weights.

Initially I had skimmed their response and found the para containing " on the information supplied by you ..." and the recommended pressures. At this point I assumed I was getting the info specific to my tyres and loading.

On re-reading I noted the e-mail was addressed to Dear sir/or Madam. the para quoted started " As a guideline ..."

I concur that we are not getting specific info from Michelin.

Where do Dft and VOSA stand on this issue of inadequate info?

I can understand that base vehicle manufacturers cannot know what bodies and tyres are fitted to their vehicles after sale and that converters do not know what tyre is subsequently fitted.
But surely the tyre manufacturer should be able and required to advise on the pressure for a given axle-lading on a given tyre.

The small upside, after the accident, is that those of us who have enquired and received an inadequate reply could not be successfully prosecuted for being under/over-inflated.

LITTLE CONSOLATION TO THE DEAD INJURED AND RELATIVES.

Some of us need to take this up. 

But how? Any suggestions?

Geoff


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## TDG

We have Michelin XC Camping 2157R16C, 113/111/Q tyres fitted 
The *Ford* tyre lable gives 50 psi front/ 80 psi rear.
We run with the front weight at about 95% and rear 90% of the max. plate weight and use pressures 50 psi front / 74psi rear.
The original tread depth was 10mm and at 14,000 mile we have 7mm from /9mm rear evenly distributed across the tread which suggests to me that we've got it about right 8)


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## Pudsey_Bear

So I now have to contact 5 different tyre manufacturers :lol: :lol: :lol: 

I don't suppose that there's a rule of thumb, dependent on the tyre dimension/rating and the axle weight not manufacturer dependent out there somewhere, so we could post it in the help section


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## steles

HI
Same tyre same size
215 70 R15 CP109R
Seems strange. i too received similar reply from Conti but very soon received this further e mail. Photos were Burstner plate

Dear Mr..................

Thank you for the photos.

You will need to use the plated axle loads as specified on the vehicle for
guidance on the correct pressures; therefore i have re-aligned the
pressures accordingly; see below.

Front Axle - 1850Kg = 4.25Bar or 62psi
Rear Axle - 2000Kg = 5.5Bar or 79psi

If i can be of any further assistance, then please do not hesitate to
contact me again.

Yours sincerely

Paul


Paul Ridler
Product Support Engineer UK & Ireland,

Now confused
Steles


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## geraldandannie

steles said:


> You will need to use the plated axle loads as specified on the vehicle for guidance on the correct pressures


I think he's assuming you're going to run at the plated, maximum axle loading, as per your plate, not the _actual_ axle loading, as measured form a weighbridge.

Gerald


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## steles

Gerald
I guess we all run at near max load but that is not the problem.
The pressures quoted were not even close.
65 psi to unclenorm max load 2060kg 
79 psi to steles max load 2000kg
Steles


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## icer

hi 
this is the information I was given in response to my actual figures.

As a guideline from the axle weights that you have supplied on the 215/75 R16 C XC Camping tyre, the pressures for those weights are as follows:-

Front axle load of 1700kg the pressure should be – 65 psi (pounds per square inch)
Rear axle load of 2300kg the pressure should be – 80 psi (pounds per square inch)

Ian


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## smick

Based on all this information, I'm going to work on the 50 + a bit on the front, and 62 + a bit on the back.

The "bit" will depend on whether I think it looks right, and whether I feel optimistic or pessimistic.

That's probably as accurate as any of the above....

Only joking....

Smick


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## TDG

smick said:


> The "bit" will depend on whether I think it looks right, and whether I feel optimistic or pessimistic....


That's my way - if it looks right it probably is right but it it looks wrong it definitly is wrong 8)


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## roger20

*TYRE PRESSURES*

I have the same tyres as UncleNorm and a similar front axles load, although the rear is much less (1765kg).

Reading similar posts over the last 4/5 years I adopted 52psi front and 62/3psi rear which seems to fit in with others.

I did arrive at the same 47psi for the front but adopted an extra 10% because I had read at some point a suggestion that because front tyres are subjected to higher braking forces, then an extra margin is justified. Thinking about this, I'm no longer really convinced by this because its continuous load that more important.

Anyway, I'm comfortable with these pressures, which may seem a tad on the high side. Whats more important to me is that after running at 60-70mph, both on the motorway and cross country they never seem to feel too warm, even on a hot day.

I might experiment with slightly lower pressures just to see whether there is a marked improvement in road noise but it would have to be really significant to make me abandon my safety margin because the new X250 Fiat is made to swing bends!


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## pete4x4

A good way of checking if your tyres are at too low a pressure is to check the heat in the tyre wall after a run out, if they feel hot then you are running too low.
Not very scientific but a good indicator.

Another way is to draw a chalk line across the tyre tread and then roll the vehicle in a straight line for 10 metres and re-check the chalk line. If the chalk line has disappeared then pressure is right. If gone in the middle but still present on the outside then pressure too high.
If still in the middle and gone on the edges then pressure too low.

The idea of the above is to get the pressure right so that all the tread is in contact with the ground, this can only happen if the tyre is at the right pressure.

Pete


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## 113016

What I find strange is that most of us are running at maximum gross weight or there about and therefore I would have thought that the sticker on the door plate would have been correct as that would have been there for commercial vans also running at the same maximum gross weight.
I don't understand how the tyre pressures can be lowered for a M/H running at the same weight as a commercial van, as weight is weight.
I run the Michelin 16inch Agilis Camping tyres and I have always run at the door pillar pressure, I know it is a bit of a hard ride over bumps and therefore I don't go charging over the said bumps and the tyres most certainly do stay cool.
My previous m/h had the Michelin 15 inch Camping tyres and also we had no problems.
7 years and neither vans tyres needed much re inflating as both held pressure very well.
But I am still listening to the advice on here.
Thanks for the thread.


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## Zebedee

Grath said:


> What I find strange is that most of us are running at maximum gross weight or there about and therefore I would have thought that the sticker on the door plate would have been correct as that would have been there for commercial vans also running at the same maximum gross weight.
> I don't understand how the tyre pressures can be lowered for a M/H running at the same weight as a commercial van, as weight is weight.


On the face of it, this logic is irrefutable. :!:



Grath said:


> But I am still listening to the advice on here.


So am I.

The insurance angle is a concern. What if one is involved in an accident and all four tyre pressures are significantly below the plated figures? :?

Is this a handy get-out for an insurer? 8O



Grath said:


> Thanks for the thread.


And from me too. 

Dave


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## Techno100

I just want my van to FEEL right. At 79 psi as plated it skates around,I can even get front wheel spin 8O . I still have 60 front 65 rear and the tyres LOOK ok but if anything maybe the rear want a tad more and the front a tad less 55 70 ?


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## 113016

Techno100 said:


> I just want my van to FEEL right. At 79 psi as plated it skates around,I can even get front wheel spin 8O . I still have 60 front 65 rear and the tyres LOOK ok but if anything maybe the rear want a tad more and the front a tad less 55 70 ?


We don't have any problems with skating or grip, but then again we do run pretty heavy as we wild quite a lot and run with a full water tank and carry everything for self sufficiency including a 2 kw geny.


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## UncleNorm

Grath said:


> What I find strange is that most of us are running at maximum gross weight or there about and therefore I would have thought that the sticker on the door plate would have been correct as that would have been there for commercial vans also running at the same maximum gross weight.
> I don't understand how the tyre pressures can be lowered for a M/H running at the same weight as a commercial van, as weight is weight.
> I run the Michelin 16inch Agilis Camping tyres and I have always run at the door pillar pressure, I know it is a bit of a hard ride over bumps and therefore I don't go charging over the said bumps and the tyres most certainly do stay cool.
> My previous m/h had the Michelin 15 inch Camping tyres and also we had no problems.
> 7 years and neither vans tyres needed much re inflating as both held pressure very well.
> But I am still listening to the advice on here.
> Thanks for the thread.


I agree with you Grath, we do run at or around maximum gross weight, but do we run at maximum axle weights? In my case, with my running weight at 3,440 kg out of 3,500 kg, my axles were Back 1,900/2,000 and Front 1,540/1,850. Although the Back axle is close to maximum, the Front seems way off!

It has been a good thread, hasn't it? Thanks to all participants!! :wink:


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## oilslick

*tried lowering*

With similar weights to uncle norm I have now tried lowering my continentals to the figure they advise.

I am assuming similar weights to ones quoted and my spec, so I have tried 51 front, 61 rear. I did not want to drop fronts all the way to 47.

The ride is much better. It was very hard before. Handling does not seem to suffer, infact I think the grip could be better. (I know on my motorcycle if the front tyre is 2 psi harder than my preference (advised figure) I can feel more drift when I push it).

Conclusions are:-

1) Continental are a good company and are more likely to have the correct figure than fiat or converter.

2) With the "Van" pressures the tyres look amazingly round!

3) With the reduced pressures the tyres have more of a "radial" look. (remember when radials camee out they always looked slightly flat in comparison to cross plies?). I have looked at a number of similar aspect ratio tyres now and believe they do look right.

4) The overall feel of the van is good. the harshness has gone and the tyres and suspension feel like they are working in harmony.

5) The tyre does have 69psi (does this mean max? it doesnt say that!) on it. Less than on the door pillar.

I will keep an eye on sidewall temperature and I will check the tread wear and tread temperatures using the thermal imaging camera from work. This is the best way to tell.

I will also keep an eye on the mpg, as this could also give an indication.

Come on SWIFT??? whats you say about your motorhomes?

Grant


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## HurricaneSmith

At a sports car meeting this morning, I found that one of the members tests various manufacturers' tyres.

I suggested that with current technology there ought to be a more robust measure of tyre pressure than "If it feels right, it is right."

He said "There is no universally agreed yardstick, and that I should talk to my tyre manufacturer."

I find that disappointing.


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## peribro

HurricaneSmith said:


> At a sports car meeting this morning, I found that one of the members tests various manufacturers' tyres.
> 
> I suggested that with current technology there ought to be a more robust measure of tyre pressure than "If it feels right, it is right."
> 
> He said "There is no universally agreed yardstick, and that I should talk to my tyre manufacturer."
> 
> I find that disappointing.


Surely the most robust measure will come from the tyre manufacturer? I believe that some manufacturers will not give advice in which case don't buy from them. I asked Continental what pressures I should use for my specific axle weights and I was given clear and unambiguous advice. The advice also tallied with the figures from Tyre Safe so I am happy that I am running with the correct pressures - which are significantly lower than those shown on the door pillar and what the dealer recommended.


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## motormouth

This is now "doing my bleedin 'ead in".
My tyres are 215/70/R/15C SAC camping and current pressures are 59 psi in front and 65 in rear. These are the pressures shown on the plate inside the front door.

The Fiat Ducato handbook states 5.0 bar for both front and rear, unladen or fully loaded. Thats about 70 psi I think.



I had it weighed yesterday and front axle is 1320, rear 1560 (total was 2920 which doesn't seem to add up)

I emailed Continental as I am thinking of replacing the tyres which are datestamped as 7 years old and the reply is that front pressure should be 43, rear 47. These seem very low to me, but I am sure they know what they are talking about, don't they ??????? 

I have given up trying to make sense of it all and I think somewhere in the middle must be somewhere near so will go with 50 f and 55 r and hope for the best. I cannot believe there is so much confusion on what is such a vital safety issue.


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## nicholsong

I have today sent an e-mail to VOSA's Press Office, in absence of any obvious direct contact, requesting help in resolving the discrepancies between info from base vehicle manufacturers, converters and tyre manufacturers (when they will give specific info.

I will advise response.

Geoff


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## motormouth

Just as a matter of interest, I was talking to a technician at a caravan service centre about the issue with tyre age etc. He said that VOSA are trying to introduce a law whereby any tyre which is 5 years old will fail an MOT, regardless of condition. This applies to cars, vans etc
He also went on to say that any MH they sell will have new tyres fitted if 5 years old.

Hmmmmmmmmmmm


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## TDG

motormouth said:


> ....................I cannot believe there is so much confusion on what is such a vital safety issue.


But there is :roll: 
We have nothing in the Chausson hand book but the Ford plate gives 3.5 bar front and 5.5 bar rear which corresponds to axle loads of 1750 Kg front and 2250 Kg rear - equating to a max vehicle weight of 4000 Kg when it fact the vehicle is plated at 3500 Kg  
Having had a clear out and rearrangement, we recently weighed 1600 Kg front and 1540 Kg rear in running order.
However, as I am getting nothing helpful from Michelin I am slowly reducing pressures to where I think they should be and am currently at 3.3 bar front ( which I will will not further reduce) and have the rears currently at 4.5bar. This has transformed the ride  
After a motorway run at circa 65mpg I recorded the following 
Road temp 28 deg C
Front tyres 44 deg C (FWD)
Rear tyres 36 deg C


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## nicholsong

Further to my post about writing to VOSA, I got a response from them referring the issue to D for Transport (Transport Technology and Standards), which I have done.

I have also asked VOSA why they, as the enforcement authority, cannot answer the Q, and how they can therefore enforce such an obvious safety issue. That e-mail copied to Dft.

I await responses.

Geoff


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## sweetie

Continental quoted me on our 4000kg Solano with 225/75/16 tyres 78psi rear 58psi front.

TDG 65mpg was it all down hill :wink: 

Steve


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## TDG

sweetie said:


> .......TDG 65mpg was it all down hill :wink:
> Steve


Steve,
One reaches the stage when you don't know your mph from your mpg - particularly after a few glasses of a nice Pino  
On the subject of tyre loading, it occurs to me that way one loads the van and the van's physical arrangement will have a significant effect on the way the tyre loads vary from the MT vehicle.
For example in our's, most of the extra weight ends up between the F & R axles so the load is distributed between the two. On a larger van however with a large rear axle overhang and a garage, you can imagine a lot of the extra weight ending up behind the rear axle. In this case all the extra weight will be on the rear tyres and the front tyres will tend to be unloaded  Hanging a scooter on the back will acccentuate that and if there is a waste water tank under there that hasn't been MTed...............


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## peribro

SvTech has a free application that you can download that lets you calculate the resulting axle loadings from fitting a bike carrier - or putting any other loading - on the rear of a motorhome. Dramatic results if you have a long overhang.


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## TDG

peribro said:


> ......you calculate the resulting axle loadings from fitting a bike carrier - or putting any other loading - on the rear of a motorhome. Dramatic results if you have a long overhang.


Absolutely - just simple levers :wink:


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## framptoncottrell

I'd E-mailed Michelin some time ago about the Agilis 81 205 70R 15C 106/104R tyres fitted to my 2006 (2002 model) Ducato van conversion. The van weighs up to 3400kg (weighbridge) depending on contents of tanks; solo travel or two of us; continental travel contents or just overnight stay. The van is almost balanced fore-and-aft with the front end heavier by about 100kgs in travel mode with full diesel and fresh water tanks.
Michelin recommended 65psi front and 60psi rear.
Sadly Michelin no longer make this size of tyre for camper vans so I've had to replace one worn pair with Bridgestones on the rear.
I E-mailed both companies again, following this forum correspondence, and received an E-mail from Bridgestone giving the recommended rear tyre pressures as 60-62psi.
Michelin 'phoned me and I had an interesting discussion with their technician. He wanted to make sure that my maximum weight on the front axle (with Michelins) was indeed 1750kgs, in which case the 65psi still stands. As I understand what he told me is that VOSA have become alarmed at the percentage of motorhomes stopped at random roadside weight-checking stations which are seriously overweight. VOSA now assume that most motorhomes are being driven in this condition and have asked Michelin (and presumably other tyre manufacturers) to recommend much higher pressures to avoid overheating and blowouts - anything up to 80psi - where the true weight hasn't been verified.

Dr (musical, not medical) Roy


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## motormouth

Are we all getting a bit paranoid about pressures?? I know I was.
But lets examine some different scenario's to try to make sense of it all.
We are told by continental that pressures should be adjusted by about 3psi for every 100kg.
Now does Mr Bus driver adjust his pressures when 10 passengers get on, does he ask them for their weights and say "hang on, I'll just have to jump out with my foot pump 'cos you lot weigh 700kg", I think not.
Does white van man adjust his pressures when he has delivered his load of one tonne? I think not.
Does Mr coach driver let some air out when he has offloaded is 50 passengers on a day trip to Blackpool? Probably not.
We see hundreds of artic's rumbling along the motorways, some empty, some with 10 tonnes on board......... need I go on.

So what's the answer?? Haven't a clue I'm afraid, but I was having a boring morning so just wanted to waste 10 minutes.


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## Bryansdad

steles said:


> HI
> Same tyre same size
> 215 70 R15 CP109R
> Seems strange. i too received similar reply from Conti but very soon received this further e mail. Photos were Burstner plate
> 
> Dear Mr..................
> 
> Thank you for the photos.
> 
> You will need to use the plated axle loads as specified on the vehicle for
> guidance on the correct pressures; therefore i have re-aligned the
> pressures accordingly; see below.
> 
> Front Axle - 1850Kg = 4.25Bar or 62psi
> Rear Axle - 2000Kg = 5.5Bar or 79psi
> 
> If i can be of any further assistance, then please do not hesitate to
> contact me again.
> 
> Yours sincerely
> 
> Paul
> 
> Paul Ridler
> Product Support Engineer UK & Ireland,
> 
> Now confused
> Steles


UncleNorm
many thanks and most appreciated. I had indeed followed your thread and became confused when Steles shared his/her correspondence from Conti.
I have chosen to load all 4 with 65psi on the assumption a little too much is better (safer) than not enough. I took the van to the weighbridge last week fully loaded (full diesel and water) with a load of 1820kg front axle and 1640kg rear.
Continental Vanco Camper 215/70/15R 109R

What do you think????

Thanks again. 

Ended up replying to wrong thread (new to all this) but hopefully UncleNorm reads this and makes the connection.    :roll:


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