I have a FS90r, and a KM110r and as far as I can say, the KM110r has a smoother throttle than the FS90r. I am not sure why, but a friend thinks it could be due to throttle linkage perhaps. My take is that Stihl sells the FS90r for light use, so it needs more throttle, and the FS130r is for all out use, so it tends to be used at full throttle, where as the FS110r is more of the middle trimmer, so it has a better throttle. The FS100rx and FS110r use the same engine, and are the only ones Stihl lists as having "quick and smooth acceleration".
If it ain't orange and white then it ain't right!
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Stihl KM110 with String Trimmer, Articulating Hedge Trimmer, and Pick Tine Cultivator
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