Glad to see you back on here HayDR! Lots of folks could use your input with hay season coming up.Most disc mowers are designed to mow above 4 mph. If you mow at slower speeds the crop loads up doesn't clear the cutterbar & the top hat the brings the hay around into the end support or grass board. As mentioned if the top hat is not functioning properly the crop drags up on the end supports and is not cleared from new crop being mowed. Be happy you have a heavy crop and adjust your speed accordingly. Sharp blades work best as well. Blades with the ends rounded off will still cut but can cause buildup issues as well. Kuhn is a fine MFG and their products work well around the world.
Some tractors have 2 pto settings 1 for most rotations and another for less rotation but more ground speed and less fuel consumption. Make sure your pro is set for highest rotation.I have a Kuhn GMD 600 that in thick orchard grass clogs on the outside corner. The grass is thick and had already put seed on.
This was last year and I’m just seeing what I might could do before this season.
It's important to be turning the implement at the designed RPM. If a tractor has more then one PTO speed, the lowest one is most often 540 RPM. The higher PTO speeds are for specific implements, however using the higher PTO speed and then reduced ground speed provides the better fuel consumption while getting near a 540 RPM.