# Tyre Pressures - WOW!



## jacder (May 1, 2005)

Just got my recommended tyre pressures back from Michelin  , as I read about this service on the forum. They suggest a significant reduction, down from the 75/80psi (suggested by the Dealer/workshop) to 50/55psi (and even lower if not fully laden to plated weight)
Any ideas as to what I should now expect in terms of ride/driving/ handling apart from it not being so hard?

Jacder


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## sersol (Aug 1, 2005)

I would have thought that 75/80 psi would be VERY uncomfortable ride.
If it were me I would inflate to about 60psi then adjust a little up or down.
After all we're not driving F1 cars.
I run at 60 psi all round on a tag axle & that gives a superb ride.
Gary


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## RichardnGill (Aug 31, 2006)

Hi, You might well find the handling of the M/H to be improved as the tyre will be able to work better as it will deform slightly over bumps Etc. rather than skipping over them. You should find that it will be more comfortable. The only down side's are you will use slightly more fuel and the turn in will be slightly slower.

The reason for the pressures to be lower is down to the axel weights of your van. The tyre is capable of carrying much more weight than it does with you van. Obviously to carry more weight it will need more pressure.

Just a thought, the rear drive tyres on most artic trucks are between 85 and 95 psi so don't worry about having 55psi in a M/H

Richard..


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## Rapide561 (Oct 1, 2005)

*Tyre pressure*

Hi

I run at 80 PSI, a Fiat Alko chassis, fully loaded upto 4000 kg. I find the ride excellent.

Russell


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## 100004 (Jul 12, 2006)

That's why the damned doors no good Russ  THe vibration from rock hard tyres :lol: :lol: Not Swifts prob at all. NOT :evil: H


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## bravocharlie (Jul 15, 2006)

I reduced my tyre pressures to 55 psi from 65/70 psi 9 months ago. This followed advice from Michelin relating to the actual weights on each axle which I provided after a trip to the weighbridge. The fully laden weight of the MH is about 3300kg. The result has been better handling, a much smoother ride and fewer rattles. Haven't noticed any difference in fuel consumption but I don't measure it that accurately.


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## davesport (Nov 12, 2006)

Hmmm, this has got me thinking. :idea: My new Hymer 644 came with close to 80 psi in the tyres which I assumed was correct. However the ride is rock solid & quite jarring & harsh. I'll drop it to 55-60 & see if this improves things.


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## bravocharlie (Jul 15, 2006)

Davesport, I would suggest having your vehicle weighed with a full load and then consulting the tyre manufacturer to get their recommendations. I think this would be the safer option and should give you more peace of mind.


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## maddie (Jan 4, 2006)

Hi Russel check your tyres! probaly say max pressure on them ? 80psi is way over !!
terry


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## maddie (Jan 4, 2006)

Hi all futher to last post I have just been out to van & have Goodyear 8 ply cargo tyres on H/Duty and in the small print on the tyres it say's 70psi MAX it also gives weights! but thats another story :lol: 
terry


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## 102160 (Dec 20, 2006)

Knaus Sunliner on a Fiat Alko chassis with a plated max of 4000kg and Knaus recomend running at ~63psi. Came with 80 in them, asked Lowdhams (Knaus importer) to check and they dropped them to 70 psi, I have dropped them to ~60 psi and the handling improved no end particulary in side winds and when being passed by trucks. MPG has remained about the same. Ride quality has improved a bit but I guess we'll never get rid of the 'crashy' Fiat front suspension problem over pot holes.

I just wish someone would do air suspension for the Alko chassis. Alko themselves have saud I can't even retro fit their own stuff. <sigh>


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## crooney (Sep 21, 2007)

*knaus sunliner 800 mpg*

Hi - Does anyone know what the knaus sunliner 800 does to the gallon. we have been told it is about 18mpg but are hoping it does more. We are picking it up on October 13th - can't wait. Never had Knaus before but it sounds good. Also first time submitting here so forgive me if i am submitting in the wrong place. Just finding my way around the site.


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## blackbirdbiker (Mar 12, 2007)

Hi, I was told that if there is a slight bulge in the wall when on a even surface, then the tyres would be at the right pressure.

Keith


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## 94055 (May 1, 2005)

Hi Crooney,
It is better to start a new thread for this question in the Knaus forum folder here

>>>Here<<<

I have posted for you

>>>Here<<<

Steve


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## THEPOET (May 1, 2007)

*Tyre pressures*

Hi, if I may add my 6 penor'th

I have a 97 Hymer B574 on a Fiat 2.5 td. My english translation of the handbook says that the pressures should be 5 bar which I have just this evening checked as 75 psi. :roll: Now when I had my previous Hymer 5 years ago I seem to remember I had the tyres running at 50 to 55 psi. I have my present van set on 55 psi. The ride is ok and my fuel consumption averages between 28mpg at least to 31mpg at best. It has jusy over 30k miles on the clock. :wink:

Cheers

Pete


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## Jean-Luc (Jul 21, 2005)

Hi Wireman, you mention Air Suspension, ah what a dream. I drive a HGV with air suspension, I wish I have on my MH as my Fiat alko A class crashes through potholes and the dash seem to go in a different direction to the rest of the vehicle. With air it feel like you are floating along independently of the suspension and road.

Regards


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## cabby (May 14, 2005)

My Autocruise Stardream a very low profile on alko chassis.2006. has tyre pressures printed in its hand book as recommended by Michelin 55 front and 45 rear.hope this will help other owners of this model.

cabby


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## sallytrafic (Jan 17, 2006)

sersol said:


> I would have thought that 75/80 psi would be VERY uncomfortable ride.
> If it were me I would inflate to about 60psi then adjust a little up or down.
> After all we're not driving F1 cars.
> I run at 60 psi all round on a tag axle & that gives a superb ride.
> Gary


For the record F1 tyres run at only about 15-16psi


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## Diver (May 15, 2005)

Just been to the weighbridge before our trip to Slovenia as we are passing through Austria and don’t want to be the wrong side of the 3500 limit before a GO box is needed.

Then phoned Michelin Technical 01782 402000 to get the correct tyre pressures.
They need to know the tyre size and axle weights when the MH is loaded ready for the journey. 

Results for mine on 215/70 R15C tyres:
Front weight 1680kg. Recommended tyre pressure = 55psi 
Rear weight 1740kg. Recommended tyre pressure = 55psi

He explained that the initial calculation for the front pressure is 52psi but then they add a percentage to this to allow for the increased weight coming onto the front axle during breaking.
He added that as the MH manufacturer doesn’t know what load will be put in the vehicle they just give the pressures for the maximum load to which the tyres are rated.

Looking forward to the softer ride.

Diver.


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## 102160 (Dec 20, 2006)

Jean-Luc, I know exactly what you mean. Alko do a chassis with air suspension but they say it can'tbe retro fitted  why i have no idea as they wouldn't enter into a conversation about it. I continue to hope that someone will develop something for the fiat/alko setup.


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## Spacerunner (Mar 18, 2006)

Most 'van converters recommend using the base vehicle tyre pressures, which as stated is usually the maximum for the tyre and type of base vehicle. The best route, and safest is to go via the weighbridge and tyre manufacturer recommendations. You can do this by email, and when you get their emailed reply, print it and then you have it confirmed in black and white to satisfy the 'Bill' if stopped for a roadside check.


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## Vennwood (Feb 4, 2007)

Hi Wireman
AS Air Suspensions Ltd are offering Air Suspension for the Alko chassis - single and tag axle. I'm thinking of investing so will let you know how I get on.
I also contacted Alko and got the same response - no they can't retro-fit however I contacted Dethleff who said they were happy with after fit air suspension and referred me to their favorite - Goldsmitte of Germany - the AS and Goldsmitte systems look kinda similar (not exactly the same as Goldsmitte appear to do several variations ) however the AS product works out a bit cheaper than Goldsmitte

I'd love to hear from anyone with experience of air suspension as its a lot of money to part with and ......


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