Open all settings (probably full countercockwise).
Look up your weight for air pressure starting point.
Using a shock pump, set to pressure, or deflate if needed to lower pressure.
Bounce the forks a few times with you on it, recheck and adjust pressure if needed.
Now set sag - I‘m assuming the Mezzer has an o-ring on the fork..if not, use a zip tie. Sit on the bike normally and lift feet off ground. Get off bike carefully, not compressing the fork further. Look for ~30% or so sag to start. You can measure it, or assume your travel # is correct, and look for the O-ring or zip tie to be at 30% of full travel in mm…from the fork seal to tie/o-ring with the fork extended/no weight on.
Add pressure if > 30%, reduce if < 30%.
Check recommended settings in chart for rebound, high speed compression and low speed compression.
Look for the #s overlapping across all 3 (downhill, enduro, trail) for a general starting point.
Rebound damping ‘slows the pogo stick’ effect when the forks are uncompressing/bike is rising back up.
Low speed compression damping is basically your smaller bumps, and high affects larger hits/jumps/drops.
The Mezzer looks like it has two air chambers - see if can find someone tling specifically about tuning this fork, or set bot pressures for your weight and follow the above for a starting point…
Can also try reading through here:
https://www.mtbr.com/threads/manitou-mezzer-owners-thread-setup-tech.1177011/
Adding - looks like when adding pressure, at least if starting from low/no pressure, you want to pressurize the IRT chamber first to be sure it extends properly internally..
