Boat Review: Riviera 51 Enclosed Flybridge

A wolf in sheep's clothing - that's the thought that came to mind as we threw the big Riv 51 into a full-lock turn while travelling at just under 30kts. At that speed, I was expecting this near-22-tonne luxury cruiser to dig in early into the turn, for the props to cavitate, and the boat to loss momentum. Not so! Not only did she maintain her speed and momentum but she went into the tightest turn I could have imagined for a boat of this not inconsiderable size.

As happens with our tests, we were off the Gold Coast in the Riviera 51 Enclosed Flybridge - a sea trial I'd been looking forward to. The Riviera 51 Series II has been around since 2008 and she's a lot of boat (three cabins, two bathrooms, big saloon, and nicely kitted flybridge), a beautiful luxury cruiser and a home-away-from-home.

POD SQUAD
It's been nearly five years since Volvo Penta released IPS. Pod-drive technology, originally developed for large cruise liners and then tugs, is now well established in the recreational market. The system is integrated with fly-by-wire steering and independently articulating pods, thereby eliminating the need for shafts or rudders. Each drive has twin forward-facing counter-rotating props, so they operate in undisturbed water.

But it's no wonder the system has proved popular, as there's lots of upside, including a marked reduction in fuel consumption, higher top speed, lower noise levels, less emissions, an increase in performance, and less physical space. Add to that joystick docking, making handling at close quarters a breeze, and you get an idea of what all the excitements about. Oh, and boatbuilders can install pod drives at a saving, too.

LESS IS MORE
With this system it's truly a case of less is more - smaller engines, bigger performance. We had three Volvo IPS600 D6 engines at our beck and call, each rated at just 435hp. These engines rev out to 3500rpm and will run continuously at 3300rpm all day in pleasure-boat mode. There was plenty of power on hand as we moved the sticks forward. The forward-facing props pulled the Riviera straight out of the hole, surprisingly fast, too, and more like a sportsboat rather than the big cruiser that she is.

On the test day, I noted that 3200rpm produced 27kts and 2450rpm 16kts, impressive performance! If anything, The Riviera 51 ran slightly nose up, but I'm assuming that's probably because there didn't appear to be too much weight up front. Generally with these types of boats there are tender and davit on the foredeck, their weight helping to bring the nose down a bit. Yet it was easily fixed by dropping the tabs slightly. After all, isn't that what tabs are for?

By now you've no doubt gathered that, in terms of performance, I was pleasantly surprised. The Riviera 51 performed well above my expectations as her agility was put to the test with a number of high-speed runs and much darting and weaving around the camera boat. With about 1.5m of swell and a slight sea during the test, she proved to be surefooted and predictable.

DRIVING PLEASURE
While the performance was exceptional, driving from the enclosed flybridge wasn't exactly a hardship either. Accessed via an internal staircase, the flybridge surroundings are luxurious. There is just about everything you could possibly want up here. I've just recently travelled from the Gold Coast to Melbourne in a Riviera 47EF and I thought that flybridge was comfortable - this boat takes it up to another level.

Two comfortable, fully adjustable helm and companion chairs face an expansive dash with stacks of room for an array of screens and instrumentation, while a large, semicircular lounge to port continues forward and finishes beside the skipper's chair.

I liked the layout because it means anyone seated on the lounge can still be a part of the conversation with the skipper and navigator. There's also a foldout table facing the lounge, which, while perfect for food and drinks, also serves as a chart table.

Just one thing, though, the electronic engine-monitoring screen was fitted to the overhead console. I found this a bit disconcerting, having to look up anytime I wanted to check the engine readouts. I would much prefer it on the dash directly ahead of me. We all agreed with that.

SPORTFISH AGILITY
Aft in the flybridge, behind the lounge, is a wetbar with sink and fridge to port and another helm station to starboard. This rear helm gives a clear view of the cockpit, over the transom and beyond, for backing into a berth or unto that big fish. Speaking of which, there was an option on this rear station called Sportsfish mode, which cuts out the middle engine so only the two outboard engines operate while facing outboard for maximum purchase.

Testing this option, we found the 51 to be highly manouevrable and responsive going astern, even when we got very aggressive and backed her up hard, filling the cockpit with water a number of times. I can imagine a gameboat skipper backing up on a big fish would find this option heaven sent and, well, even a newbie can chase fish like a pro.

While the water in the cockpit drained away quickly, we decided to go down to check that it hadn't managed to find its way into the engine room. There are lift-up hatches in the cockpit floor allowing for a quick check of the pods, but the main access to the engines is via the hinged cockpit floor that lifts via an electric actuator. A little bit of water had managed to find its way into the engine room, not too much to worry about, and Riviera later showed me a new seal to be fitted that will solve the problem.

STORAGE EXTRA
The storage space amidships, the old engine room, is accessed from the cockpit by a swing-out moulded sink, much the same way you'd access the engines on the shaft-drive version of this boat. But you can also head inside and take the ladder from a hatch in the saloon floor.

The vast area houses the 17.5kW Onan generator, fuel filters, air-conditioners, refrigeration unit, batteries, 12V and 24V battery chargers, watermaker, and everything else you would expect to find in an engine room. It is all located around the perimeter, all easy to get to and leaves a large, central open area . The fuel tank is located forward and behind the accommodation bulkhead, offering sound protection to the sleeping areas when the generator is running.

There is a bilge well located in this storage and utility space under the saloon floor and we wonder if the smell of bilge water will permeate the interior over time, since there is no watertight bulkhead between here are the new aft engine room. As the engine vents are in their usual position, outboard of the old engine room or new storage space, there are forward "breathing" panels to allow air to access the engines and to provide access for servicing.

Some of the water that had entered the engine room earlier had made it into this room through the drains in the bulkhead, dampening a small portion of the carpet, another reason to ensure that the seals on the hatches are improved (see Lockwood's box hereabouts). But as we touched on, such things should only concern the gameboat skipper preoccupied with chasing fish in reverse.

RIVIERA STAMP
Back on deck, I decided to have a look around inside. It's typical Riviera and I mean that in a good way. The quality and attention to detail is so consistently good, the high-gloss cherrywood joinery in the saloon looks superb, as does the gloss timber surround to the recessed grabrail in the headliner. It's a nice touch and a bit of style thrown in with practicality. I like that!

I also like it when, as on this boat, the windscreen is left clear and not covered over with cabinetry, as it lets in so much light to the saloon, and it's pleasant to be able to look out forward as well as through the large side windows. This boat was also fitted with (what is now a common theme throughout the whole Riviera range these days) a large, lift-up awning window and stainless steel door aft to the cockpit, bringing the interior and outdoors together as one large entertaining area.

The spiral staircase to the flybridge is just inside the saloon door and takes up surprisingly little room. We have traversed it in a seaway carrying lunch on plates. No issues there. No sandwich on the floor. There's ample seating in the saloon, too, with a dinette to starboard and a large L-shaped lounge to port.

The galley, down a step and separated from the saloon by a raised servery, is fitted out with a solid-surface bench top incorporating a sink and recessed garbage bin with cover, three refrigerator drawers and separate freezer, twin-burner electric cooktop, convection microwave, and even the standard water purifier. Lots of clever storage everywhere, including cavernous storage under the galley floor (accessed via a hatch and ladder and featuring auto lighting), and high-quality Amtico flooring assists with the cleanup.

Below decks are two elegant staterooms, both with en suites, and a third cabin fitted with two bunks. The accommodation is accessed by a long ship-like companionway that also houses a laundry with Miele washer/dryer combo and linen storage. The starboardside master stateroom is located amidships and boasts a queen-sized island bed that lifts on gas struts to reveal a large storage area beneath. Bedside tables, ample drawers and hanging space assists with extended cruising.

The en suite, with solid-surface vanity, wash basin and shower, is roomy, light and airy. The second bathroom is a similar standard and features two-door access, serving as an en suite to the VIP stateroom forward and as a communal bathroom with access from the companionway. The VIP stateroom also features an island double bed, storage and hanging space.

TRIPLE IPS OPERATION
Idling back into the marina, I was keen to see how the boat handled at close quarters and obviously how it worked with the joystick. The triple IPS with three engines operate off only two engine-control levers. The levers control the two outside engines and an onboard computer operates the centre donk, which only kicks in when both engines are engaged and go beyond 1500rpm. If you were to push only the port lever forward then only the port engine will engage at low speeds and vice versa for starboard.

I found driving the boat at slow speed, without the joystick, handled more like a sterndrive - it helps if you turn the wheel rather than just using the levers. As for docking with the joystick? Well, what can I say, for a boat that's a shade over 58ft long, docking really was a cinch, very intuitive and simplicity itself.

The Riviera 51 fitted with the IPS option is a different hull shape than the shaft-driven model, and was developed in consultation with Volvo Penta's senior design engineers. There are no tunnels, no pronounced keel and deadrise at the transom is 15 degrees.

Fitted out to a high-luxury standard, the Riviera 51 has a lot going for it. For those wanting to cruise along in comfort she is a great home-away-from-home. But with IPS she's more refined. And with the Sportfish mode, you can release her wild side. A great example of technology extending a proven boat's appeal.

Triple IPS 600s v Twin Shafts
The Riviera 51 now comes with triple Volvo Penta IPS 600 pod drives as tested here, a $75,000 option over the Enclosed Flybridge model in the standard twin shaft-drive guise using C12 Caterpillars (2 x 715hp), with the twin MTU Series 60s (2 x 825hp) with shafts an upgrade. But some 51s had C18s ( 2 x 1015hp) engines, which is to say nothing of the big Series 2000 MTU 8V (2 x 1050hp) options.

Problem was with all this, we struggled to compare apples with apples and, the deeper we went, the more confusing the sea-trial figures became. The sea trial figures for the triple IPS boat hereabouts were with a boat half-loaded with fuel and water. Those for the MTU Series 60 boat we have show a fully loaded vessel with loads more juice. There is plenty of spin out there in the engine world at present, but much of it is just that. Here's our take.

First, forget the bigger 1000hp engine options, which suffer from a power-to-weight issue and produce just two knots extra top end, but do consider the rest. If you're a pleasure boater and buying new then the pick is the triple IPS 600s. If you're in the preloved 51 market then the twin C12s and Series 60 MTUs are great. From what we can ascertain, the triple IPS seems to win out mainly in high-cruise speed comparisons against the CATs.

Add Sportfish mode (a $9272 option on the demonstrator) and this really is a manoeuvrable 'big' boat'. However, we're not yet convinced on the water tightness of the cockpit, now engine room, hatches. If you were to chase fish and repeatedly fill the cockpit with water, it could be of some concern. Tradeaboat performed reversing manoeuvres at sea and found some slight ingress of saltwater in the engine room.

Thanks to the IPS 600s and little gear or extras, no tender or crane, the Riviera 51 tested here was a relatively light ship. As such, it was a vastly different craft to the MTU-powered Riviera 51, Fascination II, that we spent more than a week living aboard on the Great Barrier Reef. That boat, with tower and all the gear, was more like a ship and, at times in heavy weather, a submarine. It was in charter, where MTU warrant its engines, whereas Volvo Penta doesn't warrant its IPS 600s in commercial applications.

You pay a $75,000 premium for the triple Volvo Penta IPS 600s over the CAT C12s. Then again, you don't need a bowthruster, which is about, say, $17,500 when installed on the Riviera 51 with shaft drives. Servicing costs are something that may vary, too - we were quoted $5023 for an annual service on the triple IPS, compared with $3800 on the MTUs, and bit less for the CATs. Insurance premiums aren't affected by the number of powerplants, we're told.

In the Riviera 51 with IPS, it's a case of new technology being applied retrospectively. We hear whispers that a purpose-design 50-odd footer with IPS is on the way. Making greater use of the interior space gained by fitting the rear-mounted engines makes sense. That big hole where the old engine room was is given over to storage, although one owner fitted a gym, and there are renderings for a crew cabin.

We still lean to the advantages of IPS drives all the same, and We understand why manufacturers like their ease on installation even more. - David Lockwood

Specifications- Riviera 51 Enclosed Flybridge

PRICE AS TESTED
$1,618,506

OPTIONS FITTED
Sportfish mode on aft docking station, dual fuel filters and water separators, extra 30m of anchor chain, rodholders in cockpit coamings, teak cockpit and swim platform, transom livebait tank, single-boom davit, Miele dishwasher, half rear-awning, upgraded upholstery package, galleyware package, and Raymarine electronics package

PRICED FROM
$1,542,779 w/ triple Volvo Penta IPS600 diesels

GENERAL
Material: Handlaid moulded fibreglass hull
Type: Monohull
Length overall: 17.73m
Beam: 4.93m
Draft: 1.2m
Weight: 21,500kg (dry)

CAPACITIES
Berths: 6 + 2
Fuel: 3300lt
Water: 710lt
Holding tank: 151lt 

ENGINE
Make/model: 3 x Volvo Penta IPS600s
Type: Six-cylinder four-stroke common-rail diesel
Rated HP: 435
Displacement: 5.5lt
Drives: IPS

Supplied by
The Riviera Group
50 Waterway Drive,
Coomera, Qld, 4209.
Phone: (07) 5501 0000
Website: www.riviera.com.au