Prior to heading off for RTE at Mundaring Weir Hotel I checked tyre pressures, front was 36, good enough for 160k return trip. Nearing the hotel the bike was like a hardly, or pig, not sure which, on checking front tyre pressure was 12psi, pumped it up to 45 for trip home, still at 45psi 3 days later.
My thoughts are for some reason the valve did not seat properly when I checked the pressures initially.
Something for others to be aware of, checking is good but can cause unwanted problems.