In 2003, Hoyt revolutionized the archery industry with the introduction of the Cam and 1/2 performance system. With the Cam and 1/2 bows, Hoyt shooters have won several national and international tournaments through the ability to precisely tune the bow for improved accuracy. Hoyt has several different models of the Cam and 1/2 system, including M4, XTR, Spiral X, Z3, C2 and Versa. Every model uses the same basic process for tuning. It may take several attempts before the bow is perfectly tuned.
Put the bow into a bow press. Compress the limbs to loosen the string and cables. Measure each cable and twist the cable until it measures 1/8 inch shorter than the listed lengths (see Resources). For example, the listed length for the 2010 Maxxis 31 with the Z3 cam is 31.25 inches. Double-check to make sure the ends of the cable are straight where the serving wraps around the cable.
Repeat step 1 for the string. Twist the string until it is 3/16 inch shorter than the listed length in the specs. For the same Maxxis 31, the specs call for the string to be stretched to 45.25 inches. Put the twisted cable and string back on the bow and release the bow press.
Tighten the limb bolts with the allen wrench and check the performance marks on the cam. These marks are two circles with lines through them to indicate where the string needs to be positioned. Adjust the control cable until the string lines up with the performance marks.
Check the brace height measurement. The brace height is measured from the bow string to the bow grip. On the Maxxis 31 with the Z3 cam, the brace height is 6.5 inches. To adjust the brace height, place the bow back into the bow press and twist the string.
Check the draw stop timing. As you pull the bow to full draw, have someone watch the cams as they roll over right before full draw. The cable should hit both draw stops--one on the top cam and one on the bottom cam--at the same time. If the bottom draw stop is hitting before the top, the top cam is under-rotated. In this case, you can add a twist to the buss cable or remove a twist to the control cable. If the top cam is over-rotated, take a twist out of the buss cable or twist the control cable.
Measure the draw length. Draw the bow until at full draw and have someone measure from the nock groove on the string to the pivot point of the grip. If the draw length is too long, add a twist to the string and take a twist out if the draw length is too short. Approximately five twists will adjust the draw length 1/4 inch.