Scaling would be bad. Mine usually take some force to roll and don’t slide by themselves. You an make sure that the tension bolts are loose. On the roller f it would be the long bolts, those control tension. Any bearing that has plastic on both sides, I call them the middle bearings, That bolt controls tension a little bit make sure they are loose. Actually make sure all the bolts are really really loose. I only sung things up after test runs to make sure it is good to go.