Riviera Yachts 51 Enclosed Flybridge SII 2008 boat specs
Riviera Yachts
Riviera Yachts 51 Enclosed Flybridge SII 2008
2008
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Riviera Yachts 51 Open Flybridge SII 2011 boat specs
Riviera Yachts
Riviera Yachts 51 Open Flybridge SII 2011
2011
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Riviera Yachts 51 Enclosed Flybridge SII 2008 vs Riviera Yachts 51 Open Flybridge SII 2011 — Same Brand, Different Boat

Matching a modified vee Riviera Yachts 51 Enclosed Flybridge SII 2008 against a deep vee Riviera Yachts 51 Open Flybridge SII 2011 means you're likely deciding between two genuinely different on-water experiences. Hull type shapes everything from ride quality and fuel burn to dock handling and resale trajectory.

On paper these two are close siblings in the size department — Riviera Yachts 51 Enclosed Flybridge SII 2008 at 54,0 ft versus Riviera Yachts 51 Open Flybridge SII 2011 at 54,7 ft. At 4 806 lbs and 4 806 lbs respectively, both sit in a similar weight class — either should pair comfortably with most mid-size SUVs and half-ton trucks, though always confirm your specific tow rating with the motor added.

The power gap is worth calling out. Rated to 1 650 hp, the Riviera Yachts 51 Enclosed Flybridge SII 2008 has a 825-hp advantage over the Riviera Yachts 51 Open Flybridge SII 2011's 825-hp ceiling — enough to notice on acceleration and at cruising speed, particularly with a full passenger load. Fuel capacity breaks the other way: the Riviera Yachts 51 Open Flybridge SII 2011 carries 977 gallons versus 713 gallons in the Riviera Yachts 51 Enclosed Flybridge SII 2008. On a lake day that's negligible, but for coastal cruising or long reservoir runs the extra range matters.

Both boats are rated for 16 passengers — a good fit for a family of four or five plus guests. Comfort at capacity is another matter; the longer hull typically means more seat options and better weight distribution.

Bottom line: Performance buyers should lean toward the Riviera Yachts 51 Enclosed Flybridge SII 2008 and its 1 650-hp ceiling. If fuel economy and quieter running matter more than top-end speed, the Riviera Yachts 51 Open Flybridge SII 2011 with its 825-hp rating is the more economical daily driver.
General Boat Info
MakeRiviera Yachts
MakeRiviera Yachts
Model51 Enclosed Flybridge SII
Model51 Open Flybridge SII
Model Year2008
Model Year2011
Measurements / Dimensions
Beam16 ft. 2 in. (4.93 m) including gunwale
Beam16 ft. 2 in. (4.93 m) including gunwale
Beam - Meters4.93
Beam - Meters4.93
Beam - Inches194
Beam - Inches194
Draft [max] - Detail4 ft. 6 in. (1.38 m) including props
Draft [max] - Detail4 ft. 6 in. (1.38 m) including props
Draft [max] - Meters1.37
Draft [max] - Meters1.37
Draft [max] - Inches54
Draft [max] - Inches54
Weight - Detail48,060 lbs. (21,800 kg)
Weight - Detail48,060 lbs. (21,800 kg)
Weight - kg21799.63
Weight - kg21799.63
Weight - lbs.4806
Weight - lbs.4806
Length - Meters16.67
Length - Metersnot available
Length - Feet54
Length - Feet54.67
Length - Inches8
Length - Inchesnot available
Length [over all with swim platform]58 ft. 2 in. (17.73 m)
Length [over all with swim platform]58 ft. 2 in. (17.73 m)
Length overall - Detail54 ft. 8 in. (16.67 m)
Length overall - Detail54 ft. 8 in. (16.67 m)
Length overall - Meters16.66
Length overall - Meters16.66
Length overall - Inches656
Length overall - Inches656
Body / Hull
Hull materialFiberglass
Hull materialFiberglass
Hull typeModified Vee
Hull typeDeep Vee
Engine and Drivetrain
Engine/s standardx2 MTU 825 hp (615 kW) each
Engine/s standard(2) MTU
Fuel tank capacity - Detail713 gal. (2,700 l)
Fuel tank capacity - Detail977 gal. (3,700 l)
Fuel tank capacity - Liters2699
Fuel tank capacity - Liters3698.35
Fuel tank capacity - Gal713
Fuel tank capacity - Gal977
Fuel typeDiesel
Fuel typeDiesel
Drive typeInboard - Twin
Drive typeInboard - Twin
Engine max1,650 hp (1,230 kW)
Engine max825 hp (615 kW) each
Operational Info
Sleeping capacity6 to 8
Sleeping capacity6 - 8
Water capacity227 gal. (860 l)
Water capacity227 gal. (860 l)
Holding tank capacity - Detail40 gal. (151 l)
Holding tank capacity - Detail40 gal. (151 l)
Holding tank capacity - Liters151.42
Holding tank capacity - Liters151.42
Holding tank capacity - Gal4
Holding tank capacity - Gal4

Riviera Yachts 51 Enclosed Flybridge SII 2008 vs Riviera Yachts 51 Open Flybridge SII 2011 — Common Questions

Which is the larger boat — the Riviera Yachts 51 Enclosed Flybridge SII 2008 or the Riviera Yachts 51 Open Flybridge SII 2011?
The Riviera Yachts 51 Open Flybridge SII 2011 is the longer of the two at 54,7 feet overall. The Riviera Yachts 51 Enclosed Flybridge SII 2008 comes in at 54,0 feet, making it roughly 0,7 ft shorter — a meaningful difference in deck room and overall on-water presence.
Which is easier to trailer — the Riviera Yachts 51 Enclosed Flybridge SII 2008 or the Riviera Yachts 51 Open Flybridge SII 2011?
For trailering, the Riviera Yachts 51 Open Flybridge SII 2011 has the edge at 4 806 lbs dry weight versus 4 806 lbs for the Riviera Yachts 51 Enclosed Flybridge SII 2008. Add a motor (typically 300–500 lbs for an outboard in this class), gear, and a partial fuel load and the difference grows. Lighter is friendlier on smaller tow vehicles and on fuel economy while hauling.
Which boat can handle a bigger outboard?
The Riviera Yachts 51 Enclosed Flybridge SII 2008 is rated to a maximum of 1 650 hp, giving it the larger power ceiling. The Riviera Yachts 51 Open Flybridge SII 2011 tops out at 825 hp. Keep in mind that maximum ratings are just that — matching the motor to the actual load and usage pattern usually matters more than chasing the ceiling.
How many people can each boat hold?
The Riviera Yachts 51 Enclosed Flybridge SII 2008 is Coast Guard rated for 16 passengers, while the Riviera Yachts 51 Open Flybridge SII 2011 is certified for 16. Note that legal capacity and comfortable capacity aren't always the same thing — on a full day out, most experienced boaters aim for about 80% of the rated number to keep things comfortable.
Do these boats require an oversize trailer permit to tow on US highways?
Both the Riviera Yachts 51 Enclosed Flybridge SII 2008 and Riviera Yachts 51 Open Flybridge SII 2011 share an 16 ft. 2 in. (4.93 m) including gunwale beam — meaning both sit right at the 8’6" threshold that most US states use for standard-width loads. In most states you can tow at that width without a special permit, but regulations vary. Always check the rules for your state and any states you'll be passing through before your first long haul.
Which boat has the larger fuel tank — the Riviera Yachts 51 Enclosed Flybridge SII 2008 or the Riviera Yachts 51 Open Flybridge SII 2011?
The Riviera Yachts 51 Open Flybridge SII 2011 has the bigger tank at 977 gallons, versus 713 gallons on the Riviera Yachts 51 Enclosed Flybridge SII 2008. That 264-gallon difference translates to roughly 792–1320 nautical miles of additional range at cruising speed, depending on motor, load, and conditions.
Are the Riviera Yachts 51 Enclosed Flybridge SII 2008 and Riviera Yachts 51 Open Flybridge SII 2011 from the same manufacturer?
Yes — both the Riviera Yachts 51 Enclosed Flybridge SII 2008 and the Riviera Yachts 51 Open Flybridge SII 2011 are built by Riviera Yachts. That means shared dealer networks, common parts availability, and consistent build quality across the line. The choice between them is essentially a question of how much boat you need, not which brand you trust.