I don't think I'll ever get the throttle body sync right on this bike. I think something is fucked by design. I can get it close, but the vacuum pull on the throttle bodies will always jump around by 1-4 kpa. It won't be dead solid like the other bikes I've done.
I've checked for vacuum leaks extensively and there are none. Crankcase blow by is not excessive. Only other thing I could think is worn valve guides but I don't see how the fuck that could be since oil changes were kept up with.

Anybody experienced something like this before?