We install a Riva Engine Breather Upgrade Kit on our Yamaha GP1800. This simple modification is used to vent crankcase pressure without redirecting the air and oil back through your intake.

To purchase, go to PWCMuscle.com:
http://www.pwcmuscle.com/riva-yamaha-...

For more information on our GP1800 build series, check out our build thread on PWCExtreme.com:
https://www.pwcextreme.com/t/yamaha-g...