Nubo
some solo cam bows have have larger idler wheels than the diamiter of the cam, some have smaller diamiter than the cam so if you measure to the bowstring on a solo cam bow and you get both sides the same measurement to the bow string the tiller will be out of adjustment.

setting the tiller properly insures that the limbs are pullung even amounts of draw weight if one is pulling uneven from the other will cause eratic arrow flight.