13 stone and Anthem x rearshock. RP2 i think.
Also i lose 10 PSI plus on screwing in pump, normal?

depends on frame setup and your weight. my pronghorn runs 230 in the RP2 because its a short travel shock and hardly has any sag.

Check the giant website for info i reckon.

and yeah, losing 10psi ish is normal for the pump in my experience, in normally put a bit more in to compensate for it.

Yep, the limit is 300psi (at least it is on an RP23) which is what I had to run the one in my ASR-7 at. It still blew through the travel too quickly as well

Make sure your shock pump is accurate, see if you can use another one just to validate the pressure you’re putting in. But 170 isn’t horrendous (although I don’t know much about Anthems)

I’m running about 210 in my RP2 on a Whyte E120…you shouldn’t have any problems

Different bikes have different geometry but as very rough rule of thumb setting the psi to match your weight in pounds is a reasonable start