1. RESTRICTOR SCREW. Locate the grub screw in the top of the rotating breech block. This is your restrictor screw. It can be used to restrict airflow from the valve to the pellet. Open it up until it's not restricting the path…just bring it back flush with the surface. The only reason we need to use it is if the velocity is higher than we want and for some reason we can't get the regulator set low enough to achieve the desired velocity.
2. HAMMER SPRING ADJUSTMENT. Remove the handle (two screws through the sides up near the breech block, and one in the bottom). Turn the now exposed nut clockwise to increase spring preload (increase velocity), or counterclockwise to reduce it. Using your chronograph, increase preload until the velocity no longer increases.
3. REGULATOR ADJUSTMENT. If the velocity is lower than you wanted, increase the regulator setting. Go a quarter turn clockwise with an M4 hex key. Now go back to step 2 and find the new maximum velocity. (Or if your velocity was already higher than you wanted, back off the regulator and go back to step 2).
Repeat steps 2 & 3 until you're about 30fps above where you want to be, then make a couple of minor adjustments to improve consistency and efficiency:
4. Back off the hammer spring until the velocity falls about 20fps.
5. Thread in the restrictor screw until the velocity falls about 10fps.
I'll attach a relevant excerpt from my book, Awesome Air Pistols from a chapter comparing the AirMax pistol to a $1000 PCP (the AirMax won).
Thanks guys, exactly the info i was looking for. i will book mark this page for reference. when it gets a little warmer im going to start messing with it. Marflow i have went through a bunch of bikes since i had my zx-11, it was a 98, then i bought a 2005 v-max, then an 02 Fz1, then an 03 R1, then a 02 zx12r, now im riding an 06 ninja 650.
down sized a see i'm 69 as a few days ago and pushing the ZX-11 out and getting it turn around is get to be a task i have a 1979 Honda CBX 6 cylinder that has 16,000 miles but it needs the carbs rebuilt and don't have the money or can i find someone to work on it
good luck on your pistol setup and take care
mike wolfram