What Spiker said. Adjusting for idler lean should make the string come off the back side (toward shooter) straight. Because the the bow has a cable slide the string will be pulled off at an angle on the back side (toward the limb). The shorter the bow the more severe the angle will be and this is normal.
Is the string served where it rolls over the idler? If not I would highly recommend you serve it. Working at Cabelas I would think they have all the materials you need.
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