Went through a process of elimination.
K&N airfilter back to std = no change.
New plug = no change.
Std header pipe & torpedo silencer back on = no change.
Now with the bike back to as delivered I spoke with the dealer who agreed to hook the analyser up and see if there was anything obvious.
It had to hapen didnt it, its around 20km trip to the shop, with the problem getting worse as I rode when at about 15kms problem all but dissapeared.
As expected dealer could not find any issues.
Put my Hitchcock header pipe and silencer back on and it is running fine.
I am at a loss as to what may have caused this issue.
Perhaps some condensation on connectors somewhere