I have a M800Sie, with SIL High Mount exhaust.
The bike, under WOT in the upper end of the rev range 7-9k is amazingly rough. The gauges start to shake and are unreadable, but nothing is violently bad. Just not how I would expect it to be. Its a used bike to me, and my first bike. I would expect some roughness in a 2V twin, but its excessive. Local shop degreed my cams, TB sync, tps adjust..no help. The only comment I can make, that I did reset the cams to factory assembly setting, and did not tighten the belts up as far as they should, and it ran super smooth, but felt like power dropped off in the top end. That may have just been the lack of vibration energy making it feel like less power.
Any thoughtsÉ
I am waiting for a PCIII to arrive, hoping the fueling may be off from the SIL pipes and causing this