ZX7R does not start after spark plug change

Hello dear people, I did not find any mail exactly to my problem. I wanted to get my ZX7R Bj. `96 out of hibernation last week, unfortunately it did not jump on. Instead, it is still drunk to me. Since I, a friend of mine, changed the spark plugs only 2-3 weeks ago, I would exclude these times. I let the carburettor run empty in the last fall, therefore I can not imagine that it is clogged. The spark plugs have I changed, since I had always had problems with that last year, when it came cold out of the garage, half an hour in the sun and it went on wonderfully. The spark plugs also looked really bad. Now to the battery, not the best anymore, although only a year old, but since it shrugged this morning briefly I would say, it might not be the battery either. I also had to warm them up with the (not laugh please) hair dryer so that they came. During the se I didn’t know where it came from. In another post I read that you should let the swimming chamber run empty. Where do I find the screw exactly? Bzw. is that possible without building the motorcycle apart? I hope someone can help me, since I don’t even come to the workshop……always thank you in advance. Greeting Sebastian P.s. It’s embarrassing to me, but I can’t help myself. someone has to say how the gas tap has to stand to stand on? Since it smelled like gasoline last week I would say he’s open, but maybe he’s on reserve