Citroen Specials Club - the club for all lightweight cyclecars

I want to replace the old rear 125R15 68S tyre on my 223. The 68 rating is 329kg @ 36psi.
Having done some simple measurements and assuming 2 passengers at 80kg each and dog in the boot, the load on the rear wheel is about 310kg. ( front tyres ~200kg each)
Using standard inflation tables the tyre then requires approximately 33psi for that load (ignoring any other characteristics).
I am considering a 135R15 72S with a max loading of 355kg @36psi running at about 32psi.
Has anyone used this tyre on a 223 and at what pressure?
The extra width of the tyre is no issue, but will the slightly increased diameter (~8mm) be a problem?
I have also seen reference to running the rear tyre at 22psi; that seems very low for the potential load.

Yes, I run these tyres on my 223, a Toyo on the rear wheel and Michelin ZX on the front. When I first put these on the car, on Burton Bugatti style wheels, the tyre fouled the bodywork at the rear on bumps. I relieved the grp a little, about 10 mm max I think. I run the rear tyre at about 30 psi and the fronts at 28 psi.

Hi Ron,

I run Michelin 135R15 ZX tyres front and back - no clearance issues.

I must admit I have just noted what previous 223 owners have listed and compared to std 2CV specs - then 'calculated' suitable pressures... So I run with 23 PSI in the front tyres and 35PSI in the rear single tyre ( I have never actually weighed the weight on the rear tyre)

The tyre wear appears even across the treads, so not showing any signs of under or over inflation.

I be interested to see any Pressure v Load guidance you have.

Steve