It isn’t that similar, except that both are 650 v twins.
There are no interchangeable parts.
The Hyosung GT-650R is a good bike for racing with a heavy but solid frame that makes it an excellent corner carver. Some buddies of mine in England have raced them at Brand’s hatch and it will embarrass most Japanese bikes in the turns. We’re hunting for the right set up to embarrass them on the straights as well.
You are right, the engines do look a lot alike and the HP is similar, I think the Suzuki revs higher.