Compound bow strings are put under significant tension as they transfer energy from the bow's limbs to the arrow. The strings, comprised of multiple strands, should be replaced at least every 12 months or 5,000 shots. A worn string can break without notice and cause serious injury to the archer. Replacing a string on a compound bow requires the use of a mechanical bow press that flexes the bow's limbs to take tension off the string and cables so the string can be replaced.
Setting the Bow in the Bow Press
Place the bow in the bow press and loosen the compound bow's bottom pins where the limbs meet the riser.
Tighten the bottom pin-adjustment screws on the bow press.
Place the bow press' retaining bands over the the limbs, securing the bow to the press.
Adjust the left side pin on the press, so it contacts the bow's limb approximately 1/2-inch below the cam, then attach the side bar to the piston.
Count the number of holes on the left side bar to replicate a symmetrical connection when repeating the connection of the right side pin and piston. You are now ready to begin applying pressure to the bow limbs.
Replacing the String
Turn the bow press crank clockwise. This will raise the piston and flex the limbs, taking pressure off the bow string. Only turn the crank enough to slightly loosen the bow string.
Remove the old bow string by pulling each end of the string from the holding pin on each cam.
Lay the old string next to the new string to ensure you are using the correct size. Make sure the new string has no broken strands. If it does, use another string.
Place one end of the new string on the cam pin and wrap the string around the bottom cam, letting it sit on the cam's groove track.
Pull the other end of the string over the top cam, seating in the groove track, and then secure it on the top cam's pin.
Turn the bow press crank counterclockwise to release the flex on the limbs and add pressure to the string. As you gradually put pressure on the string, check each end to make sure it has a solid connection to the cam and no slippage has occurred.