Pumped up the tyres this weekend and thought I'd check the space saver. The recommended pressure was 4.8 Kg/65 lbs - more than double the pressure of a normal tyre! My tyre was only pumped to about half that.
I managed to get it up to about 3.8kg with my foot pump. The pump clamp burst way at about 3.5 but at 3.8 pumping was very hard and seemed to be the max I could get to with a weak foot pump.
I expect with such high pressure the rate of leak is also high so the spare will need pumping up regulrly. Might even stress the valve if I keep the pressure at such high levels. Might be better to drive around with the pump in the back