Muddy Breaks: Inside Claude Clayton’s 2015 Sea-Doo RXP-X Bolt 85 Project


“But, it’s only like, two bolts!” Claude Clayton protested emphatically. “It takes me 15 minutes to swap it out.” Yes, the Sea-Doo X-Team racer had a point, but we stood our ground that the average enthusiast wouldn’t be as comfortable with swapping out a supercharger with an Engine-Tech (ET) blower as readily as say he, a seasoned racer, or tuner, and thereby wasn’t a “bolt on” part. We had been debating the definition of what made a “bolt on” part for 10 minutes by now and hadn’t paid much notice that our food had arrived.

We met Clayton earlier that morning to finally take a ride on his yearlong “Bolt 85” project. Within weeks of his near season-ending injury at the first round of the 2015 AquaX series in Daytona Beach, Florida, Clayton contacted The Watercraft Journal about his plans to build a competitive Pro Open closed-course race boat that runs a staggering 85mph while being fed E85 fuel. The numerical theme was also to be carried further by completing the machine with (or less than) $8,500 in additional “bolt on” parts. We even teased it back in May.


Above left: The custom-mapped Sea-Doo X-Team E85 Race ECU maintains us the the iBR and iControl display. Above right: A deep Clayton-Spec designed saddle is covered by Jettrim.

Clayton’s road to mending from a shattered ankle and crushed larynx required a succession of surgeries resulting in the 34-year-old living with a handful of titanium hardware holding his neck and foot together, respectively. Clayton and his wife also welcomed their newborn daughter, which in turn, pushed the project back further. It was completed in time for Clayton to participate in both the IJSBA National Championships (that shadowed Round 6 of the AquaX series) in Cocoa Beach, and the first Pro Watercross World Championships in Naples, FL.

When it finally came time for Clayton to trailer the Bolt 85 to Counce, Mississippi, for our photoshoot, it was still in its closed course configuration as it had competed in Naples; meaning its prop, sponson and handlebar configuration were exactly how Clayton preferred it for closed course racing. But conditions wouldn’t match those of Florida; December on the Tennessee River offers less than ideal conditions for pretty much anything, as air temperatures lingered at 46 degrees, making the on-the-water temp 36 degrees.


Above: The incomplete AquaX season decal marks how Clayton’s injury at Daytona Beach benched him for most of the season.

The water surrounding Pickwick was rough, with 3-foot rollers and a brutally cold southbound breeze unbroken by the barren treeline. This made searching for enough flat water to collect a decent top speed number almost impossible. Having cut his teeth at the family lake house just a few miles south towards Eastport and halfway towards Muscle Shoals, Clayton directed us towards Cooper Hollow, one of countless inlets that become “party coves” when the weather is more favorable.

“Sorry for getting here so late,” Clayton apologized as we snapped pictures. “I had to run across town to the ethanol station to fill it up.” Converting the Sea-Doo from traditional gasoline to ethanol required some work, particularly to the fuel system; a Walboro 255 fuel pump, a RIVA Racing Fuel Pressure Regulator, massive 1000cc injectors and a custom-mapped Sea-Doo X-Team E85 Race ECU allowed the RXP-X to operate on the alternative fuel. While many tout the environmental benefits of E85 (were you to disregard the fact that E85 increases the emissions of acetaldehyde), its weak overall popularity has made finding it at times difficult.


Above left: A modified RIVA Racing steering neck features a custom DESS key mount and low-profile KX Pro Taper bars. Above right: Black ODI grips replace the factory rubber.

Yet, many performance enthusiasts have found the fuel incredibly receptive to high compression and big boost (psi) engine combinations. Replacing the Sea-Doo’s cylinder head is an unported Judge Motorsports Race Head that has been slightly milled, increasing the engine’s compression to 9.5:1. The addition of the aforementioned ET 68-140 supercharger increases the overall boost to a consistent 18psi at 9,100rpm. Although E85 characteristically burns cooler than traditional gasoline, a large RIVA Intercooler and RIVA Flame Arrestor were added to chill the intake charge. Lastly, a custom-built Judge Motorsports Waterbox replaced the stock exhaust.

A 155mm Judge Motorsports Impeller features an aggressive pitch that together with a Sea-Doo X-Team Intake Grate launches the RXP-X from a dead stop or from the apex of a turn with gecko-like traction. A modifed RIVA Steering neck holds a set of low-profile KX Pro-Taper Bars wrapped in black ODI Grips, that together with a special home-brewed pair of Clayton-Spec Sponsons gives the Bolt 85 the best steering input-to-execution handling we’ve ever encountered on a stock RXP-X hull.

Above left: Converting the RXP-X’s Rotax 1503 to run on E85 ethanol required some doing, including converting to 1,000lbs. injectors, a Walboro 255 fuel pump and a RIVA Racing Fuel Pressure Regulator. Above right: A Judge Motorsports waterbox replaces the factory exhaust and a large K&N conical air filter replaces the BRP air induction box.


In fact, even in the brutish chop along the Mississippi/Alabama border, the Bolt 85’s ability to bite and snap corners was impressive. Typically, we’ve found stock-hulled RXP-X’s to struggle in wide sweeper turns, but not so with the Bolt 85. Equally, the immediacy of power-upon-demand helped propel the ski through tight hairpins that otherwise would require a little more finesse. It was the explosive throttle response that truly made the Bolt 85 an experience. “It’s making about 350-ish,” Clayton shrugged. “My turbo boat makes about 100 more horsepower.”

Slinking as low as we could into the custom-shaped Clayton-Spec Jettrim seat, even inside the cove, with water so clear you could see the rocky bottom as you sped along, we could only manage 79.4mph. Clayton’s lighter frame and familiarity with the racecraft fared better, fetching an 80.8mph top speed. “The other prop got us up to just over 83mph,” he explained. “This prop is really set up for the closed course, and comes on a lot harder.” A point that didn’t evade us.


Above: The sponsons are deceptively simple in design but make a huge difference in how the RXP-X’s stock hull behaves. Removing the winglets and a large portion of the rearward trailing surface allows the Sea-Doo to stay engaged in large sweeping turns and keep it from searching while maneuvering through chop.

As one can deduce from the list of high performance parts listed, Clayton’s definition of “bolt on” gets a little murky. Despite coming in just under the targeted top speed and a hair above the budget, the Bolt 85 project delivers on power, handling, and seat-of-your-pants excitement. Both Tim Judge and Clayton toyed with the idea of offering the Bolt 85 as a comprehensive package allowing enthusiasts to recreate the project at home. With some fine tuning, Clayton is positive he can meet his goals and we look forward to seeing the results.


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Kevin Shaw

Editor-in-Chief – 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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