This modification utilizes stock exhaust system with catalytic converter in place. Stock flame arrestor case is retained, but internal screen and forward mounted plenum chamber are removed. We do not recommend the use of aftermarket flame arrestors in conjunction with stock exhaust system with cata lytic converter. Our testing has proved that heat produced by the catalytic converter can cause engine damage when stock flame arrestor is removed. Stock oil injection system can be retained.

No internal carburetor modifications are performed. "Tamper Caps" are removed from high and low speed carburetor adjustment screws to optimize carb settings.

RIVA Performance Cylinder Head is installed. Head features 41cc domes that produce 145-150 psi compression (valves down). Girdled head design securely clamps cylinder down preventing potential cylinder cracking possible on modified motors.

Note: RIVA also offers a modification service for your stock cylinder head. This consists of decking and redesigning the combustion chambers. This modification will produce performance similiar to the RIVA Perform ance Head, but does not provide protection from cylinder cracking.

RIVA GP1200R Free Flow Exhaust Kit is installed. Kit replaces restrictive sound suppression system located between waterbox and hull exit reducing backpressure and engine operating temperatures.

RIVA GPR Ride Plate and GP1200R Top-Loader Intake Grate are installed. Our rideplate and intake grate combo increase top speed and significantly enhance handling characteristics. Prop spin and cavitation found with the stock grate is greatly reduced along with the modified GPR's tendency to drop on its nose when the throttle is let off at high speeds.

RIVA GPR Pro Pump Seal Kit is installed. Location specific molded inserts are siliconed into the voids of the OE pump inlet shoe significantly reducing cavitation.

After extensive im peller testing we found the Solas 13/19 Concord to be the best all around impeller for stock thru Stage I GP1200R's. Billet impeller nose cone included.

NOTE: Stage I Kit for Competition Use Only.