Stihl FS111R is sluggish

Looks like the problem has been resolved. Turns out it was a carburetor problem of some sort. I almost gave up and was going to take the trimmer to Stihl and let them figure out what the problem is. Then I remembered that I had a small bottle of Mechanic in a Bottle sitting on my shelf and I said to myself, give it a shot before you take it to Stihl. I put a tablespoon of this stuff in the gas tank and started the trimmer and it was limping along just like it did before, but all of a sudden after about 5 minutes or so it showed signs of running a little faster and the rest is history. After doing about an hour's worse of trimming by the end of that time my trimmer was running like a bat straight out of hell. Frankly I couldn't believe it. That potion actually did what the bottle said it would do, clean up everything inside, dissolve gum, soften flapper valves etc. I will check it again in a couple of days, but I am pretty sure a dirty carburetor was the problem. That wonder potion is still in the carburetor now and working.