You would have to make a base line reading of your oil temp,with your perfectly jetted bike,at a know air temp,at a repeatable road speed,on the same test road,for the same amount of run time.But unless you dupe those conditions every time(except For jetting of coarse),no way,and even then it may not be sensitive enough to see a difference.But if your bike is perfectly jetted you really do not need to know much,now do you.A directional,point source temp gauge aimed at the same spot on the head would probably have a much better chance of seeing elevated cylinder head temps.
Al
