There is no loss of power or anything like that. There are no obvious issues with the linkages either. It's only when moving in either direction, when you take your foot off the treadle it snaps back to almost neutral, but not quite. The tractor will continue to creep until you tap the treadle again to get it in a neutral state. I've read where other owners of this model, like Billrog, have had Kioti take it back and split the tractor to replace something - with varying results. Kioti has taken others and replaced the damper spring with a stiffer one - with varying results. The damper probably just tempers the spring's return rate so, on second thought, it's probably the spring not the damper that I would be playing with. I did adjust the spring a bit, but it didn't impact the 'step of treadle and doesn't return to 100% neutral' issue. Here are the parts in question that I can mess with.

