Bring the tire PSI up to 15psi or more and you'll see a big improvement in top speed...not only does it provide slightly taller gearing but rolling resistance is cut way down, and handling is improved at those speeds to boot.
I gained a solid 15mph by airing my tires up to 20psi with my LTR, and at least that much with my 250 running 30psi.
Higher speeds need higher PSI.
...and of course all of the tires say never inflate past something like 10-15psi, but who gives a damn LOL
Not going to buy street tires for 2 or 3 rides down pavement.