Originally Posted by HardWorkingDog
[warning: way too wordy. the tl;dr summary: replaced spark plug, added speedoDRD,
bike had major high rpm stutter about 10 miles later, but after stopping and turning back
seemed to run fine...any ideas???]
My guess is you got some anti seize or dielectric grease on the electrode of the spark plug. Once it burned off, it stopped causing an issue. Ran in to similar situations occasionally on my cars back when I still cared enough about 4 wheeled vehicles to wrench on them myself.