Everyone seems to think that the 19,23, and 25 hp models have the same displacement as most are led to believe by the incorrect information that hustler provides on their product specs. I am sure that this is just a misprint, but this is the information straight from the Kawasaki website: 19hp = 35.7 cu. in. or 585 cc. 19hp @ 3600rpm and 36.6ft. lbs. @ 2000rpm Weight = 71.2lbs. 23hp = 41.2 cu. in. or 675 cc. 23hp @ 3600rpm and 39.8ft. lbs. @ 2400rpm Weight = 88.2lbs. 25hp = 41.2 cu. in. or 675 cc. 25hp @ 3600rpm and 41.3ft. lbs. @ 2400rpm Weight = 90.2lbs. So it can be seen that these are not the same engines with different carb settings. While the 23 and 25hp motors are the same displacement the the 19hp is on 585 cc's and weighs almost 20lbs. less than the other two engines. I hope this helps clear up some people's confussion among these tricky kaw power engines.