Hi, I have a 2017 Z125 Pro that I just took out of winter hibernation. I filled the gas tank and added stabilizer before the winter. It takes a good 30 sec for the engine to fire up when cranking it. Cycling the key a few times to prime the fuel seems to help. There was a CEL on the first startup which has since gone away. The bike runs great once started; no issues at all. I read somewhere that filling the gas tank too much might cause this. Which is what I usually do 🙉 I thought it might be bad gas, so I refilled after about 100 miles but it's still occurring. I should add: bike is stock. Spark plug, air filter have been replaced recently.