Is my Honda producing the right top end?

Is my Honda producing the right top end, its a Honda Lead 80CC (NH80) "1983" completly stock
And im only getting 40mph on the flat, out of it not much for an extra 30cc as the jog did 32mph!

Does anybody know anything about these scooters as theres very limited info on them on the net!

I,ve had a look at the transmission and the rollers are slightly squared off and the clutch is coated in rust would this cause a lower top speed?

And is there likely to be any restricters fitted as its not 16yrs learner legal?

 

when was the last time it had a full engine rebuild? have you tried a top end overhaul? it could be dodgy rings causing your compression to be low