I've had the bike for a year and only been able to put ~2K miles on it, mostly due to the cost of keeping this thing running.
In the time that I've owned it: 2 batteries (1 under warranty), reg/rectifier, stator, flushed fluids, oil change (shop used semi synth...), spark plugs, tyres, valves were inspected by dealer.
The electrical issues are mostly sorted, but it does still sputter and stall if I start riding it too soon after start up (less than 2 minutes or 4 bars on temp gauge).

Anyway, the biggest problem I'm having right now, the bike overheats quickly if it's not moving. I've had several sensors replaced, including thermo switch sensor from ktmtwins and radiator has been flushed several times with Engine Ice. I assume the shop did the coolant flush correctly, since they mentioned having to raise the front end to get the air out. Previously, the fan would not turn on, but the sensor replacement fixed that. Initially, with the new sensor and Engine Ice, the bike ran well for the first 100 miles. Now it overheats within 5 minutes of riding if I'm stopped at a red light. The shop advised that there's too much of a black residue built up in the radiator and they believe that is the reason it is overheating; radiator is being blocked by the residue. They believe the water pump is operating fine. The temp bar gauge quickly maxes out all bars with red lights flashing. The temp degree however, seems to be okay as it stays in low to mid 70s and doesn't seem to match up with what the temp bars are at.

How do you know that engine temp is less than indicated on gauge?

If it is, has the engine temp sensor, lhs at base of cylinders, (not the fan switch sensor at radiator) been replaced?

If it’s not and temp gauge is accurate, does radiator remain cool(ish) with engine running and, therefore, has thermostatic valve been checked?

The whole cooling circuit can be flushed and back flushed with a hosepipe, far more effective than just several changes of coolant run through by the water pump only.

My temperature gauge used to shoot to the top and was sometimes wildly erratic. Turned out it was a cracked connector at the top right of the radiator.