Not necessarily. For many years, up through 1997 I beleive, the European countries legally limited all motorcycles to a maximum of 100 horsepower. To this day, France still observes this limit. So, if your potential ZX-7 is a French one, it would actually be down on power. There is talk about the European union re-imposing the 100hp limit again.
Nowadays, and for the last several years, European emissions regulations have in fact been much stricter than the U.S. standards.
However, it sounds likely that the 1998 model you are considering is unrestricted. Incidentally, an unrestricted model sportbike in Europe is no less or no more powerful than the ones we get here. They are in the same state of tune.
As mentioned, the trick really will be to get it through U.S. customs. Registration and titling might also be tricky. Honestly, it really is more of a headache than it's worth unless you are getting a smoking deal on the bike.
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