So here we go (XT660Z/2014) ... 16kkm and running like a tractor or wild horse, surging (specifically at about 2500revs) and stalling (usually when pulling the clutc ... driving me NUTS. Close to selling that f..ing thing.

Was running smoothly until a month ago :-(

Got the diagnostic tool from Europe -- 70Euros seemed reasonable and read out the ECU values last weekend: TPS = 17-97 and CO=-2

I played with the CO values and had the impression that putting CO to -4 or -6 would smoothed the bike's behavior but it's still cutting out (specifically when pulling the clutch)

Where to go from here??? Love the thing too much to let it go.

Got the ECU in front of me:
11D8591A-00 on the front label

COD Motore 11D-E9001-10 on the (very faded) back label

white stamp on the front (11P // 5J)

Any hint what ECU this is and if it was replaced?

Thanks
Thomas

Forgot to mention: No faults shown from the ECU (apart from lean sensor but that was the guy at the WOF throwing it when it stalled on him/history reset fixed that)