What is the most likely root cause of the ~5000 rpm/~70mph vibration? Ignition curves, tb imbalance, or just something elementally resonant about the engine and chain? Adjusting the latter seems to alleviate it a little. I have noticed it more since installing the 2012/13 R map. My tb's were balanced according to the map sensors, but I haven't tried swapping or checking them for offset.
On using gauges...I was always a fan of analog gauges when tuning Italian twins. They were especially indicative of maladjusted throttle cables as one gauge would rise as the other fell until the adjustment was perfect. Are digitals that much better?
Originally Posted by Zuber
The MAP sensors are often not matched exactly. You can read the voltages when the engine is stopped and then try to balance and adjust for this difference.
I've found using the MAP sensors to balance is very frustrating. TuneECU only updates the display every 1/2 second or so. Also, the values jump all over the place. I can balance with an electronic gage in 2 minutes and know it is right on. I've spent a half hour with the MAP sensors and couldn't tell if it was balanced or not.