Unit was working fine. I raised the front enough (using my hoist attached to the front of the frame) to change the blades, all went well. When I lowered it it started normally but went into a sharp right turn when handle were in normal position. I could go straight with the bars held offset a few inches, so I mowed a little to see if it got any better (or worse). No change. Everything looks ok as far as oil levels (mine has the two reservoirs). All I could think was air pocket? so I did the air bleed procedure but no change. Yesterday I loosened the handle adjusting screws completely for full movement and the right side is still slower than the left, quite a bit. Before all this started, at full speed this mower would blow what little hair I have back. Now when adjusted to go straight it's maybe 70% of the speed it used to go. I put a new drive belt on it several months ago, all was fine. Visually the units look identical on the outside as far as the movement of the travel from the handles to the input mechanisms. I'm in a small town and let's just say I don't think I want the local shop tearing into the drives. Serviced with Hydro Gear filters and 20-50 synthetic oil at 75 hours. Thanks in advance for any thoughts.