GPZ750 Gearing

[Eastoe]

Registered my 82 GPZ750 2 weeks ago and did a 520 chain conversion using GPZ550 sprockets.
I guessed the gearing and put on 16/40 sprockets which was a lot too low so I changed the front sprocket to 17.
Still feels a bit low or perhaps the loud exhaust is making me want to keep the revs low.
At 4000 revs in top i'm doing 90klm. 110 klm in top is 4800 revs.
Has anyone got the same or similar bike with standard gearing to tell me what revs your bike is doing at those speeds and how you like it.