Hi, I’ve been driving a KTM 250 EXC-f for quite a while and am very happy with it. Now I got a used lc4 with it, but I just can’t get it to run properly… After I started it for about 5 hours she ran, then ran it for about 15 minutes, then turned it off, after that I wanted to start it again, which should not be a problem with a warm engine. Unfortunately, this didn’t work. After my leg was already blue I then got the Carburettor removed (Dellorto PHM 40 SD). I was able to discover a break point on the holder or version of the external nozzle. So I bought a used carburettor (about 20000km running) on eBay – no improvement. As a result, I checked ignition, also because everything was ok. I noticed that it smells extremely like gasoline when kicking, which was not ignited. This made me conclude on a wrong level of float. After setting the Sc hwimmers still no change. Slowly the ideas run out of me, I also have only 2 guesses: 1. The nozzles and seals in the carburettor are too worn out 2. The piston rings are through and thus the compaction too low. Does anyone have any other ideas? Unfortunately I have no experience with the 620. What would you advise me to do? Thanks in advance.