Moomba Mobius XLV: Performance Report

Moomba Mobius XLV: Affordable tow boat is fully equipped.

By Staff

January 28, 2004

With its engine turning 4,800 rpm, top speed for the Mobius XLV was 44.7 mph. (Photo by Tom Newby)

Based on everything the new-for-2004 Moomba Mobius XLV delivers, from a three-bag water-ballast system and a wake plate that create outstanding wakes, to its versatile seating configuration, you couldn't call it a ?mid-level? 25' (including the add-on fiberglass swim platform) tow boat. And yet its as-tested price, less than $40,000, with these goodies and more, puts it squarely in that category.

Lose the five options—water-ballast system, wake plate, stereo system, tower cover and engine upgrade—and you're looking at $35,995. Even at that price, the Moomba Mobius is plenty of towing machine with a color-matched trailer, a single-bag ballast system, a tower and more. That makes it a true bargain, at least in the pricey tow-boat world.

Towed Sports

Though the Moomba Mobius XLV certainly can handle slalom-towing duties, it is, above all, a wakeboard boat. That explains its V-drive configuration, tower—dubbed the Rad-A-Cage by the builder—ballast system and wake plate.

The plus side of the three-bag ballast system was that it distributed water, some 1,000 pounds of it, evenly throughout the boat. Two bladders in stowage compartments flanked the fuel-injected 320-hp 5.7-liter Indmar Assault. A third bladder was located in an in-sole locker.

The downside of the setup was that the bladders, when filled, took up most of the stowage space in their respective lockers. But then, with the large locker behind the observer's seat, optional racks on the tower and stowage compartments under most seat cushions, the Mobius XLV hardly lacked for places to stash gear.

Combined with the wake plate, a Bennett trim tab mounted on the aft section of the boat's 11-degree hull, which had spray rails and a sharp chop-cutting keel that gave way to a small delta pad, the ballast system produced infinitely variable wakes. Our expert wakeboarder couldn't get enough of the giant crests when the system was full and the plate was down. But he also appreciated that the wakes could be adjusted to the skill level of the individual rider.

Of course, for ski testing we emptied the system. Surprisingly though, a touch of negative plate trim improved the boat's slalom wakes by ?softening them up,? in the words of our professional skier. Though our skier felt he could pull the boat slightly off line in hard turns, our boarder couldn't budge it. Both said the pull out of the hole was strong, and both praised the water-level fiberglass swim platform with its nonskid surface.

Performance

Our ski-test team took advantage of the morning glass on the Colorado River in Parker, Ariz., but by the time our lead test driver and co-pilot climbed into the Mobius XLV, the water had roughened up. In river slop unsuitable for wakeboarding—forget skiing—the boat delivered a smooth ride, at least for a tow boat.

With its engine turning 4,800 rpm, top speed for the Mobius XLV was 44.7 mph. It reached that speed in 20 seconds. Time to plane with the wake plate down was 2.3 seconds. It took 6.7 seconds for the boat to run from 20 to 40 mph. Strong numbers, all.

In all turns, the boat felt connected. It didn't twitch or bobble, and never hinted at sliding. Tracking was true at all speeds and steering-wheel torque was light.

Workmanship

The lamination recipe for the handlaid Mobius XLV was substantial. Backing its lustrous gelcoat was a 20-mil vinylester barrier coat, 1 1/2-ounce mat, a layer of Magnum ceramic and 1708 biaxial material and 18-ounce woven roving sandwiched in 1 1/2-ounce mat. The boat's foam-filled stringers and sole were bonded with polyester adhesive and then glassed in place with 1708 biaxial fabric and vinylester resin. Like the red and white gelcoat, the mold work was clean.

Hardware included a navigation light on the nose, the tower, a ski-pylon and grab handles. Notably absent were cleats, once taboo on tow boats but now fairly common for good reason—they make life easier.

Installation of the boat's engine using lag bolts and a rail system was standard production fare, as was the engine-compartment rigging. Several items, such as valves for the ballast system laid on the shift cable for the transmission, were left unsupported. Though the installation was by no means poor, it was not up to the generally high workmanship standards we observed throughout the boat.

Interior

For the Mobius XLV, the manufacturer borrowed an innovative seating concept from its Supra line. A convertible seat/filler cushion in the walk-through created a forward-facing seat in the bow playpen and a rear-facing seat between the observer's bench and driver's bucket in the cockpit. Very clever.

Starting at the observer's position to port, a U-shape lounge ran all the way to the back of the bucket seat. That made for plenty of open, carpeted sole. In addition to the large locker behind the observer's station, which included a glove box that held the boat's Kenwood AM/FM CD stereo (Sirius radio also is an option on all Moomba tow boats), there were good-size compartments under the lounges.

Privately labeled gauges with a Moomba logo were aligned above the tilt steering wheel. An Insta-Trim lever on the steering column controlled the wake plate. Rocker switches for the accessories and a remote control for the stereo were to the right of the wheel.

Overall

There's much to recommend about the Moomba Mobius XLV beyond its relatively low price. It offers great wakes for riders of all levels, plenty of open space and seating, generally strong craftsmanship and steady performance. You can spend a lot more on a towing machine, but you won't necessarily get more boat.

Hull and Propulsion Information

Deadrise at transom	11 degrees
Centerline	25' (with swim platform)
Beam	8'2"
Hull weight	4,100 pounds
Engine	Indmar Assault 320
Cylinder type	V-8
Cubic-inch displacement/horsepower	350/320
Lower-unit gear ratio	1.46:1
Propeller	OJ Legend 18" x 14"

Pricing

Base retail	$35,995
Price as tested	$39,680

Options on Test Boat

Upgrade to throttle-body injection ($1,295), hydraulic wake plate ($795), Bertha three-bag ballast upgrade ($650), Rad-A-Cage logo cover ($550) and AM/FM CD with remote ($395).

Test Conditions