Will the Empulse's top speed be gearing dependent or computer controlled? If it's limited by gearing then a set of different sprockets might be fun to experiment with at the track!
The Empulse will likely either be controller-limited, gearing-limited, or artificially restricted by a governor of some type. The Empulse 10.0 has a higher voltage than the 6.0/8.0, and the 8.0/10.0 use higher amp-hour modules (which should be able to tolerate higher peak and continuous current draws) than the 6.0.
Since the top speed is listed as the same for all bikes, it's probably geared for maximum acceleration and a top speed just above 100 mph. Assuming the bikes are not restricted by a governor or a weak controller, the Empulse 10.0 at least should be able to go somewhat faster than 100 mph on track.