There has been much discussion about ATA and setting it properly. I have had many bows that needed tuning and one thing I have noticed is that rarely is there any consistency in how the idlers are aligned. This is due to the cable harness settling after the initial setup. Every single bow that I’ve tuned has exhibited excellent flight characteristics with the following method:
I max out the limbs to take my spec measurements. I press the bow and take the cable loop and twist until the ATA measurement on the shelf side corresponds to the following specs:
28″ for the Creed XS
30″ for the Creed
30″ for the HeliM
28″ for the Z7 Xtreme & Tactical
32″ for the Z7 Magnum & EZ7
30″ for the Z9
30″ for the Z7
32″ for the Reezen
29.75″ for the DXT
29.75″ for the Hyperlite & Passion
33″ for the S2
37″ for the Drenalin LD
33″ for the Drenalin & DR2
31″ for the Switchback XT
Once this is set with the limbs maxed out I look at the cam to see where it’s orientated. I adjust accordingly until the timing holes run parallel to the bowstring putting equal twists in both loops of the string to maintain the balance of the factory twist. After this is done I set my nocking point so the arrow sits perpendicular to the string. I then set my centershot to 13/16″ at the berger button.
Once this is accomplished I run an arrow shaft flush with the bow arm side of my idler wheel. I then twist the cable harness so that a gap of 1/16″ to 1/8″ exists between the shaft and the string at the nocking point. At rest the idler is canted inward from the riser on the top and outward at the bottom but at full draw it’s straight up and down. A good rule of thumb to get you very close to right on is to use 12 full twists on the harness side where the quiver mounts and 9 full twists on the opposite side.
Every one of these bows that I’ve tuned like this has had excellent results. From this point, walk back tuning is a great way to dial in centershot to an ever greater degree as well.
Here’s a great link to learn about walk back tuning
I have been fighting this wheel lean issue for a while. I can always get it into the right spot but the discrpancie between twists on either side always seems to high. Right now my Z7 has 11 on right and 4 on left. Is that OK? ATA and timing hole tune is perfect.