Tier 4 rules were crammed down the throats of the manufacturers (and customers) by the omnipotent EPA. Maybe Kioti could have done a better job implementing it. Have other builders done better? I don't know. But seriously, considering the few gallons of Diesel fuel most of us burn, Tier 4 is a joke and the joke is on us.
Yep! Here's hoping Trump gets them in line so this kind of bureaucratic BS doesn't screw us over as often.