30 front / 34 rear sounds about right, manufacturers generally recommend higher values at higher speeds, …would be interesting to see if it changes much with high altitude, you could test that better than most of us For comparison, I ride a much heavier BMW K100RS and the one up numbers are 33/36, two up 36/42 and two up riding above 180 kph calls for 39/42. In my experience too high pressure results in your suspension over reacting to even the smallest road ripple, and on gravel roads it feels unstable owing to the reduced foot print, very low pressure is most noticeable in the rear first when it starts to squirm, even traveling in a straight line. I encountered a rear flat at high speed once, riding two up! …couldn’t figure out why it was under-steering and felt like the bike had a hinge in the middle, until I stopped and looked down to see the rear tire totally flat. Thankfully it was the rear tire, we were both very light weight riders, both very experienced, so nothing bad happened.
Now for something completely different; on my competition trials bike I ride 5.5 psi in the front and 4 psi in the 2 ply tubeless rear, but then in trials you seldom ride faster than 30 kph and you want only enough air pressure to keep the tire on and not dent the rim when you hit the big sharp rocks