To determine if you lose by a cylinder you should inpece the spark plugs if they are with the symptoms of an oil loss by the cylinder. As a question, don't you have leaks outwards? I recommend that you make a gas exam. Report me to see how you are going.
You already do not know any system so that the injector butterfly does not make me is annoying noise, apparently it has a little game due to the km that the motorcycle has ............ Thank you