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Speed is intoxicating. It's visceral. A kind of thrill that appeals to your senses at the most primitive level. Once you've experienced it, there's no turning back. Like any other rush, it's a fix you want again…and again…and again.
No problem. Except speed doesn't come cheap. Especially on the water. To put yourself into the magic 70-mph-plus echelon, expect to pay about $100,000 for a 26' single-engine offshore-style go-fast. That's about $1,429 for every mile per hour you want to fly. Is high price the necessary consequence of high performance? Maybe. Then again, maybe not.
If the boat has to be big, be prepared to pay big. But if you're a true velocity junkie, if the gut-level thrill of speed is simply the result of how fast you can rocket across the water - and you don't care how you get there - we have your ticket to ride. You'll not only go fast, you'll feel as if you're approaching Mach 1. Plus, accelerating to that top speed will be like driving a nitro dragster, leaving you with a wind-stretched grin for the few seconds it takes for the speedometer to register those magic digits of 70...and beyond. The best part is that you get all this for the price of a blue-light special. How does paying only around $170 for each mph sound to you?
Want speed for less? Here's the ultimate bang for the buck.
The Price of Speed
The boat that does all this is one you sit on, not in. It's a waterbike. The one we'll work with is Sea-Doo's popular two-passenger RXP. However, there are plenty of other bikes capable of hitting our target with the most minimal of investments.
At the RXP's heart is a 1,494 cc four-stroke, single overhead cam engine with four valves per cylinder and multiport fuel injection. It produces an impressive 215 hp, much of which is the result of a centrifugal supercharger with intercooler. In stock form, it runs reliably in the 67-to-69-mph range with a light load. Right out of the box you're already scratching the underside of 70.
But I intend to build upon these stock credentials by turning to the premier waterbike performance shop in the nation, Riva Motorsports in Pompano Beach, Florida (877/748-2926). Several years ago, Riva powered a Yamaha GP-1200R WaveRunner into the Guinness record books with a speed of 87.5 mph. The company claims to have pushed waterbikes into the 90-mph range. But rather than opt for its vaunted custom-tuning expertise, I'll keep things simple by installing one of its inexpensive Stage I performance kits. With it, Riva promises to push my $11,199 2007 RXP beyond the 70-mph mark for the bargain-basement price of $674. Boat and mods combined, that's about one-tenth the cost of a 70-mph offshore go-fast.
To my surprise, the components required to push the RXP this fast are relatively straightforward and require little more than a few hours of labor and an upgraded diet of 91-octane gas.
One of the biggest boosts comes from Riva's Power Filter, an air intake system that replaces the more restrictive stock intake. Essentially, it's a 3"-diameter J-shaped duct capped with an oversize K&N filter. The Power Filter is supposed to improve acceleration and raise rpm by feeding the supercharger a healthy supply of cool air.
The remaining mods will be done at the craft's pump. A thin two-degree wedge will be placed between the pump stator and the output nozzle to trim up the nozzle, raising the bow of the craft while underway to reduce drag. I'll also be swapping out the stock impeller for an aftermarket Solas model pitched specifically for this application. The final component is Riva's top-loader intake grate. This grate protects the pump from debris and adds a reverse wing to more effectively load the craft's pump, a design modification that is said to eliminate most prop spin and cavitation.
All together, Riva owner Dave Bamdas claims this package will put me close to 72 mph. A tall order? Let's find out.
