RIVA Water Box for Ultra

Developed on in-house dyno and extensively tested on the water, this waterbox features rounded tips and exhaust tubes for optimum exhaust flow. A unique exhaust baffle will increase low-end horsepower and mid-range pull on your Kawasaki watercraft. Delivers up to 15 hp on modified engines along with significant torque gains. High-strength aluminum construction will survive backfires and meltdowns. Powder coated to prevent corrosion. A must have for modified engines. Includes detailed installation instructions.

Main features:

Delivers up to 15 hp on modified boats.
Machined pipe flanges for reliable coupler retention.
Radiused exhaust pipes and tips.
Powder coated to prevent corrosion.
Additional application requirements:

2014 and newer Ultra 310: Eliminates restrictive second waterbox. Requires RIVA Free Flow Exhaust Kit (Part # RK16110 ) and RK15-2.38/3.25 Coupler.

2011~13 Ultra 300: Direct replacement for stock water box. Use with stock exhaust tailpipe or RIVA Free Flow Exhaust Kit (Part # RK16090-08 ).

2008~10 Ultra 260/250 Models: Replaces restrictive stock water box. Requires RIVA Free Flow Exhaust Kit (Part # RK16090-08 ).

2007 Ultra 250 Models: Eliminates restrictive 2nd water box. Requires RIVA Free Flow Exhaust Kit (Part # RK16090 ).

Note: Not designed for use with non-supercharged Ultra LX models except 2023 and up.