RIVA Sneaks Out 2nd Gen Top Loader Grate for GP/VX Yamahas

Last week, the world record for the fastest personal watercraft was set at 135 miles per hour aboard a GP1800R SVHO. Certainly, there wasn’t a whole lot left “factory stock” on that machine, but the hull and deck were more or less as Yamaha produced from its Newnan, Georgia manufacturing facility. Add to that an incredible record of GP1800R  sweeping podiums since its introduction in 2017, and it’s clear that these WaveRunners are favorite of performance enthusiasts.

In 2019, Yamaha made some minor changes to the GP musclecraft; first, being the addition of the “R” and the inclusion of a top loader intake grate and an extended-surface, inverse-straked ride plate. Last year, the GP1800R was redesignated as the “GP1800R SVHO” as the VXR became the “GP1800R HO” – a mouthful to say the least. Additionally, the GP received a redesigned two-piece pump, with a 160mm liner and impeller, and a tapered stator measuring 155mm at the inlet and 160 at the exit.

Above left: This is what the factory stock GP1800 intake grate looked like in 2017 against the first iteration of the RIVA Racing top loader intake grate. In 2019, Yamaha “borrowed” RIVA’s design but found that while it was an improvement, more was left on the table. Above right: RIVA’s second edition top loader intake grate has a massive scoop grate and an even larger inlet, providing the GP1800R unmatched hook up, reduced cavitation and all without losing speed!

Yet, one of the biggest issues plaguing the GP1800R SVHO was initial cavitation at the onset. From a standstill, the GP1800R fought to bite and launch hard. And while the GP1800R could track straight even in rough water, staying hooked at throttle was still a chore – primarily due to the craft’s light weight. To directly combat these specific issues, RIVA Racing launched the second version of its performance top loader intake grate for all GP and VX Series Yamahas.

Dave Bamdas explained, “This grate was developed through our racing efforts and used by the RIVA Racing Team to win multiple championships over the past 18 months.” The most prominent feature is the radically increased oversized top-loader wing and optimized inlet ramp to reduce cavitation, as well as the giant opening at the “chip” permitting more water into the pump area for continued hookup with zero top speed loss. Cast from stainless steel, it won’t rust and it’s super durable too. Priced at $329.95 it’s the ultimate weapon to perfect launches and remain hooked all the way through your pull.

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Kevin Shaw

Kevin Shaw

Editor-in-Chief – kevin.shaw@shawgroupmedia.com Kevin Shaw is a decade-long powersports and automotive journalist whose love for things that go too fast has led him to launching The Watercraft Journal. Almost always found with stained hands and dirt under his fingernails, Kevin has an eye for the technical while keeping a eye out for beautiful photography and a great story.

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