back to basics / tyre pressures

There is the feeling that with any fix, always start with the basics.
I looked at my bike and the rear tyre looked low. Touching the side wall i could tell the pressure was low. Next i turned the wheel checking the grooves and found a rusty nail.
The cause of my handling although now i still need to set the shocks as i have started to change the settings.
So, start with the basics is my advice. I assumed it was the shock rushed in and forgot to check the pressures. I guess one of the first things. Also my front tyre pressure is low. The biposto should be 2.2 and rear 2.4. I found only 24lbs in the front and 22lbs in the rear.
Vinny