As part of my never-ending rebuild I replaced the throttle tube that the image is referring to, I'm not sure how that would relate to the problem you describing but its a 10-minute job and the actual part is really cheap so to replace that isn't going to set you back majorly. I put the link below to the vid I followed, maybe watching him do it and checking yours, you can fault find, before buying a new throttle tube. Hope that helpsI get one interesting problem. First I tune voltage on throttle position sensor. It should be 0.68-0.72v at idle. When I open throttle several times and get it back voltage becomes more or less than normal. After that engine makes pops&bangs or even shut off and I can't start it. I'm sure that there is a problem with gas handle. Look at the part number. Suzuki updated position 1 and position 2 on the picture
https://www.youtube.com/watch?v=Yi5jR7zEOoE
a smile for our rabbit ! 2015 is EFI, no carb. just adjusted valves a couple of weeks ago because of the same issue and indeed they were all out of tolerance. Note: it was already a pain to start before.. Recently checked tip over sensor, AT sensor, water temp sensor etc.. all looks fine. I suspect the ignition coil... my resistance readings are a bit lower than spec. I have ordered a new ignition coil that should be here this week. If not starting, next is to see fuel pump and injector for a clean. FYI, it was sitting for 12 months and I forgot a bit of fuel inside the tank… so maybe clogged lines? 12 months ago it was starting… strangely even with valves out of spec it was starting not at 2nd but maybe 4 or 6th kick... take care mate!