TAV-30 Max speed limit?

[Possom point]

salsbury 330 or comet 340 are rated to 8500 rpm.

Would you have to have an adjustable jackshaft for this set up, As in you can move the JS forward and backward?

 

[deejaaa]

i've been clocked at 50. stock warrior sprocket and TAV 30 with GX390.