I wouldn't have thought this was what it was designed for.
Probably 40-50 MPH on average.
If you are going to use it like that it maybe worth a sprocket change so it is not revving itself to death.
But at 65-70 MPH it is doing pretty good.
C30F Power Up needle
2 turns out
Baffle out, Screens In
It starts,it runs,it gets to where all CRFs can get to without the valve or valve plate dramas