These compass tyres say to inflate to 20psi.
My pump is a bit old and knackered so I stopped when the gauge got to around 18 / 19 and the tyre felt hard
(it’s just an old car pump that I had in my garage for the last 20 years)
When I did the tyre swap, I tried to use only tools that I’m likely to (eventually) carry around on the bike with me for puncture repairs etc. what surprised me most was that the spanner that comes with the bike doesn’t fit the rear wheel nuts. Take an adjustable out with you fellas and be prepared to fight your tyres back into position.
A top tip from you tube was to have the wheels lying brake disc up, but the rear wheel has important stuff either side so I needed to fit this tyre upright.
I would recommend trying this at home before in the position of needing to do it at the roadside / in the woods or similar so you know what you’re getting into