More top speed out of a dirt bike ?

[Justin]

Besides changing the sprocket, what can be done to raise the top speed of a 4 stroke yamaha 125l ?

I want to be able to get at 65+ while not holding it at full rev.

How can I sacrifice more torque for top speed ? Is it possible to change the gearing ? Any other basic mods similar to a sprocket swap ? 1 less sprocket tooth means greater top speed correct ?

 

[Joshua H]

change the front sproket by 1 tooth more ( it equals 4 rear teeth) for more top speed. change the rear for more get go