Shaking at high speed

My 2001 tib is vibrating violently at exactly 70mph - 85mph. The steering wheel shakes and the car feels to vibrate a bit too. What could the problems be so i can fix them? The tires are fairly new, i am running yokohama lowprofiles. The rims are stock as with everything else on the car. I am just ready to sell the thing and i want this shaking to stop before i do so.

get alignment fixed, and tires balanced.

if that doesnt work, then post again, but do that FIRST!!!

plus with low pros youll feel alot of bumps but yes realingment and balance

Dont worry, that is a problem with every hyundai, expecialy the sporty ones. Just do everything that has been said above and you should be fine!

..it happens with every car... even the sporty ones

I am going to try and get it aligned and balanced this week , i will let you know of the outcome.