hard to start

Hi! My Husaberg 650 02 model is starting to annoy me... Off with the head, disassembled all the valves and cleaned everything. Grinded valves and seat, mounted it back together and filled the ports with liquid to make sure that there was no leak. Assembled the head togheter with new seals...

I've got a 98 FC501. It won't start after running for 20 minutes and I thought it was the magneto, valves or other things. But it does start after sitting for a couple days (4-6 kicks). . It appears the plug is oily and wet and black. The carb settings are probably not well tuned and the...