But for those enthusiastic 750SXi owners and productive aftermarket performance shops, Kawasaki did leave a lot of room for horsepower gains in the SXi's engine. With the 750SX limited pipe, the engine produced 78 horsepower, as measured in the lab again. On the water, which is what we riders really care about, the slightly modified 750SX gained substantial top end and midrange power. Like the stock 750SXi, the stock 750SX was equipped with an exhaust system designed more for a quiet ride than a high-powered ride. Again we commend Kawasaki, and other manufacturers for designing quiet exhaust systems, and leaving the extra power for the aftermarket manufacturers.
Most states have similar regulations regarding the noise level of a watercraft.
The legal limit for noise is 82dB in Minnesota, California, and most other states. Check your state's boating laws to know for sure. The exhaust gas exits the pipe in the center of the expansion chamber, not at the end. This centerbleed design lets the sound wave build the best performance while keeping the noise to a minimum. The 750SX was a popular watercraft for enthusiasts as well as aftermarket parts builders.