Here is a nice little conundrum for all you 912 fans: Background: Engine & aircraft 849.5 Hobbs Hours (doing 50 hr oil change & inspection this coming weekend). Symptom: Within the last two flight hours, my tacho (a Rotax original) had developed an intermittent hiccup/pulse (clockwise or if you like increased rpm by about 100-200 rpm) right through the rev range. Other: Nil other symptoms. All engine gauges indicate normal. Have noticed no change in engine performance. Runs very smoothly without apparent hesitation. Ignition check L/R - Both normal. I had thought a loose connection but wouldn't the gauge rpm drop, rather than rise?? Any ideas/suggestions????