Hello All,
I'm having the exact same problems with my bike. I took the carb apart to clean it and I still have the same issue where the engine cuts out at low revs. I have seen the video above already however the carburetor on my bike is different from the one in the video so I'm unsure what to do next. When I deconstructed the carb it didn't appear that the choke was something you could open manually as the pivot point was held in place by a permanent fixing. The throttle cable appears to be the only thing that is able to open the valves on the carb. I am probably going to need to take it to the garage to see if they can fix the issue. My best guess is that the throttle cable needs to be re-tensioned or replaced. If I find out what the problem is I will try and post it on here.
Wish me luck!