Two-strokes run into thermal problems with large bores. We can get by with them on a freestyle application. Couch racers had a difficult time keeping 80-82mm pistons from burning up at 7500 rpm. Remember that our big twins only work with big pumps since they cant turn as much rpm. Using modified Superjet engines is a cheap evolution that most jetskiers can accept. If we started from a clean sheet the 701 would be as relevant as the WR500 engine is.