I'm talking about the 3 Z877 shims that go in between the bearings on the input shaft. Actually, in looking at the instructions (page 15) it shows the 3 shims on the bearing further from the bevel gear. I put them on closer to the bearing closest to the bevel gear to eliminate the problem. I guess you can play with this. Try to get the gear as close as you can without it binding. Hope this helps