# Tyre pressures. I've been on the phone to Michelin.



## davesport (Nov 12, 2006)

My van came with the recommendation from Bhills to run the tyres at 80 PSI. This was the rated maximum pressure for the tyres. (Michelin 215/75/R16C 113/111 Q)

The ride was incredibly bone jarring & uncomfortable. I lowered the pressures to 70 PSI all round & this was a whole lot better. I've had the van weighed several times now & the very helpfull tech dept at Michelin have given me the following pressures.

[hr:da902a8582]
*Van unladen*
Front 1740 Kg Max Press 55 PSI	
Rear 1740 Kg Max Press 50 PSI
Total 3480 Kg.
[hr:da902a8582]
*Fully loaded*
Front 1850 Kg Max press 60PSI	
Rear 2150 Kg Max Press 65PSI
Total 4000 Kg

The gentleman from Michelin says the equivalent van tyre under the same maximum load would never be inflated over 69 PSI so I've no idea where the 80 PSI figure originated from :twisted:

The difference is night & day. Why did'nt I do this before 

D.


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## EJB (Aug 25, 2007)

It's the only way to get the right answer.
So many posters offer so many opinions when there is an easy and definitive answer only a phone call away.
I even think that answers on 'tyre pressures' shouldn't be allowed on the forum.....that would go down well!!!!!!!!!! :roll: :lol:


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## Rapide561 (Oct 1, 2005)

*Michelin*

Hi

I totally agree about getting on the blower to Michelin.

I do however run at 80 psi and the tyres fitted are "OK" with this - as per telecon with Michelin. I do not mind a hard ride.

Michelin's number is 01782 402000 and ask for the technical department.

Russell


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## Solwaybuggier (Mar 4, 2008)

Sure I've seen the suggestion that it's even better to weigh your van, loaded, at weighbridge and email details to the tyre manufacturer asking for recommended pressures. Print off the reply and keep it in the van (with weighbridge printout) so that if you should get any problem you can brandish the email.

Not done it myself yet but I plan to next time we're out loaded.

As for where the 80psi comes from, on our van there's a Fiat sticker on the doorpost suggesting that. I think there was a thread about these stickers recently?


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## wilse (Aug 10, 2007)

Our Hymer Van 572 also has a sticker claiming 80psi, when it went to Ford for it's last service... they were ca*king themselves, as they normally do inflate this highly... and we have Michelin Camping tyres.


Wilse


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## davesport (Nov 12, 2006)

> I do not mind a hard ride.


Lets keep this clean Russell :lol:

D.


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## ingram (May 12, 2005)

As a slight aside: I have been checking tyre pressures today ( on my car) and found that the gauge on my compressor varied widely from my small hand gauge: hand gauge 30psi; compressor gauge 35psi. I then checked with another old style hand gauge and that showed 30psi. near as dammit too. So I decided two out of three is good ............. when I find my other, other gauge, I'll check with that one too: pays not to rely on just one gauge .......... unfortunately my hand gauges don't rgister high enough pressures for the motorhome.

Harvey


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## 101405 (Oct 15, 2006)

Over Inflated Tyres are likely to generate excessive heat and and Fail .(ie )Blow out! also a tyre over Inflated will wear quicker as it takes on a round tread apperance, The Information given on side wall of Tyres is mostly for the US! As motorhomes are built mainly on Lcv's chassis . which are deemed to have a MAX gross weight for most of its running life.So a cross between running empty and running at its capacity is drawn. the vehicle Mfg will establish this figure with its tyres suppliers.this will be a little on the hard size as an under Inflated tyres is is even worse.so its best to use the vehicle Mfg's Inflation figures , which is on one of the door pillars or on the vehicle plate. remember these tyres are not just fitted to M/H' they have lots of different applications hence the max . Psi/Bar rating.


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## buffallobill (Sep 28, 2007)

ingram said:


> As a slight aside: I have been checking tyre pressures today ( on my car) and found that the gauge on my compressor varied widely from my small hand gauge: hand gauge 30psi; compressor gauge 35psi. I then checked with another old style hand gauge and that showed 30psi. near as dammit too. So I decided two out of three is good ............. when I find my other, other gauge, I'll check with that one too: pays not to rely on just one gauge .......... unfortunately my hand gauges don't rgister high enough pressures for the motorhome.
> 
> Harvey


i have found the same problem , different reading from the compressor gauge, at a garage, to the pressure readings checked on my digital tyre pressure gauge, always take my digital reading to be the true one .


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## GetDuffed (Nov 28, 2006)

Hi D, the 80lbs pressure might have come from it being stamped on the tyres as on my Michelin X Camping XC -225/65/R16 stating 1120Kg @ 550Kg Pressure 80 psi cold, it does give a hard ride and certainly the shakes over pot holed roads - Mick


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## nickpl (Sep 16, 2008)

Overinflated, excess wear in the middle. 

Underinflated, excess wear on the edges....


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## Rapide561 (Oct 1, 2005)

*Tyre pressure*



davesport said:


> > I do not mind a hard ride.
> 
> 
> Lets keep this clean Russell :lol:
> ...


Ooops!

Ok then, I don't mind a bit of clatter on the cat's eyes!

Russell


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## EJB (Aug 25, 2007)

Quote:-"so its best to use the vehicle Mfg's Inflation figures , which is on one of the door pillars or on the vehicle plate."

The vehicle manufacturer has no idea about the specification of the finished MH so how can they possibly recommend tyre pressures?????

As I stated earlier:-"It's the only way to get the right answer. 
So many posters offer so many opinions when there is an easy and definitive answer only a phone call away. 
I even think that answers on 'tyre pressures' shouldn't be allowed on the forum.....that would go down"


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## Wizzo (Dec 3, 2007)

Have to agree with you EJB.

I have a strong suspicion that the door pillar sticker with an inflation figure of 5.5bar (80psi) is on virtually every Motorhome produced by Fiat / Peugeot etc. It cannot be right for the vast majority of motorhomes on the road and indeed I consider it to be potentially lethal in some circumstances.

If there's anybody out there with a door pillar sticker that's different please shout up.

JohnW


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## Bella (May 14, 2005)

*October is Tyre Safety Month*

PeeJay and I have both posted this info recently but as it is relevent again;

Check out this website for data on tyre pressures according to motorhome axle weights.

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

Pam


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## GTI-PIP (Jul 1, 2007)

*Tyre Pressures*

I agree with Davesport, My hymer handbook said 80 psi.
When I first got the van I ran them with that pressure it was like having no suspension ( not nice ) so dropped them to 70 psi all round.

That was much more comfortable but now I shall try the 60-65 psi. We have done just over 30.000miles thru europe in the last three and half years, and have replaced the 2 front tyres the inside of the tread on both went first with the remaining still had about 3mm left.

Off to the Global Rally so I best give our 1 bed flat on wheels a clean.

Cliff


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## bognormike (May 10, 2005)

That pdf from the link is excellent. on the table it gives for our tyres at the absolute top weight 4.16 bar (60psi). The table shows that 80psi should only be used on driven rear wheels, and then only when the axle load is 2300kg (on a 215/75R16 CP /113).
The Pilote handbook gives 5.5 bar (80psi) as well as the hymer ones above!
I've just had 2 new Michelin Agilis camping tyres on and told the guy 65 (4.5 bar); I think I'll test it out like that & see what the ride is like - also check the front ones & adjust as necessary.


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