I wish I had found this before the countless other videos out there that skip the barrel adjustments and go straight to adjusting the upper and lower limit screws which, unless you are one of the rare viewers who for some reason are installing new gears on your bike for the first time, will unnecessarily mess up your gearing system making the process much more complex. So in other words, if you have a new bike with gears already installed and the gears need adjusting due to normal new cable stretch, just follow this tutorial.
Outstanding. Video identifies the condition, and where to fix it. By coincidence, had the "ticking" noise on my last road ride on my mountain bike. Turned out, the my local bike shop adjusted the derailleur with the barrel all the in, preventing me from adjusting on the fly, in the direction needed. At home, I put the chain in the smallest cog, loosened the cable at the derailleur, unscrewed the barrel adjuster midway, then retightened the cable. Then used the barrel adjuster to stop the ticking. Thanks for the tutorial!