A good Tyre sales/specialist will know as they stock all sizes and have to inflate on replacement....

I have had these size tyres on for 3 + years, I couldn't find any info either, through trial and error I think I settled with 36psi front 42ps1 back. I think I based this on the little sticker on the door at the biggest tyre they did, the 20" and at a fully loaded pressure. I did this pressure when I was towing and left it up there and it has been running fine.
As everyone says it is trial and error as they are not OE but I would personnally be interested what the X5 recommends on a 22" RIM, so please post or PM when you have an answer.

Adam

mmm all these tyres pressure seem low i go 48 psi on front and back on 20" found that to be best drive and best fuel consumption.

? r mine too high now me thinks

I recently got this answer from Michelin in connection with our Motorhome and it makes interesting reading:


The Michelin product quoted is able to run at the following axle loads/pressures, when fitted to a 'single fitment' axle (one tyre only each end of axle):

215/75 R 16C 113Q 'XC Camping'

Axle weight Pressure
(Kgs) (psi)

Quoted wts: 1500 44 Front, Plated
Quoted wts: 1500 44 Rear, Plated
Quoted wts: 1500 44 Tag, Plated

+10% front below minimum:
Normally, we would suggest an increase of the front tyre pressure by 10% above the final calculated 'static' value, to help the front axle tyres cope more easily with the weight transfer forward under braking (providing the maximum pressure, 80 psi, is not exceeded). The static axle weight provided is so low, however, that the minimum pressure level should be considered as having this 10% already included.

Final recommended pressures:

Front: 44 psi
Rear: 44 psi
Tag: 44 psi

Plated axle weights:
Have you verified that each axle weight for your vehicle is actually being run at or below these quoted 'plated' weights, by visiting a local weighbridge?

* The above pressure values are only recommended for the axle weights stated above.

We suggest that individual axle weights from weighscale readings are used, in order to calculate pressure recommendations for each quoted load condition. These would be preferred, due to readings being taken in the actual vehicle 'running' condition - that is to say, with all water/fuel/baggage & passengers etc. onboard - and may result in better comfort if the vehicle is running way below maximum capacity.

The results of roadside surveys indicate that some motorhomes have been found to be overladen, especially the rear axle, with potential for subsequent tyre related problems.

The overall tyre industry, therefore, tries to build-in a safety factor by fitting specific, strong 'motorhome' tyres, inflated to high pressure, in order to remove the potential for consequences of overloading &/or under-inflating the tyres.

One 'overall' weight is of no use in calculating tyre inflation pressure levels, since the vehicle may appear to be within the maximum permitted, but in reality may have the rear axle severely overladen & the front axle very lightly laden.


Thank you for your interest in Michelin.

Yours sincerely,
Michelin Tyre Public Limited Company