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Brief Summary
The Neptunus 650 Fly is an ocean-going luxury cruiser. Semi-custom built to the owners’ specifications in St. Catharines Ontario, this 66’4” motor yacht blends performance, comfort, and strength with a high quality of fit and finish.
Key Features
- Fly bridge wrap around seating with storage below
- Fly bridge port side table with 4 stainless bar stools
- Aft deck BBQ unit with cover
- 4-burner ceramic stovetop, microwave, refrigerator drawers, and freezer/icemaker drawer
- Dinette seats 6 people with large cherry wood table
- Built in 14” LED flat screen TV with custom cabinetry
- King size berth with memory foam mattress
Test Results
RPM | MPH | Knots | GPH | MPG | NMPG | STAT. MILE | NM | dBa |
---|---|---|---|---|---|---|---|---|
600 | 6.4 | 5.6 | 3.5 | 1.8 | 1.6 | 1810 | 1574.2 | 67 |
1000 | 11.3 | 9.8 | 14 | 0.8 | 0.7 | 799 | 694.8 | 73 |
1250 | 12.6 | 10.9 | 30 | 0.4 | 0.4 | 414 | 360.1 | 75 |
1500 | 15.8 | 13.7 | 46.5 | 0.3 | 0.3 | 336 | 292.5 | 77 |
1750 | 22.2 | 19.3 | 67 | 0.3 | 0.3 | 328 | 285.2 | 80 |
2000 | 27.7 | 24.1 | 95.5 | 0.3 | 0.3 | 287 | 249.7 | 82 |
2200 | 33 | 28.7 | 113 | 0.3 | 0.3 | 289 | 251 | 80 |
2250 | 34.6 | 30.1 | 118 | 0.3 | 0.3 | 290 | 252.4 | 81 |

Specifications
Length Overall |
66' 4'' 20.22 m |
---|---|
Beam |
16' 7'' 5.05 m |
Dry Weight |
78,000 lbs. 35,380 kg |
Tested Weight |
83,505 lbs. 37,877 kg |
Draft |
4' 8'' 1.42 m |
Deadrise/Transom | 19.5-deg. |
Bridge Clearance |
20' 7'' 6.27 m (max) |
Fuel Capacity |
1,100 gal. 4,164 L |
Water Capacity |
300 gal. 1,136 L |
Total Weight |
83,505 lbs. 37,877 kg |
Acceleration Times & Conditions
Time to Plane | 6.9 sec. |
---|---|
0 to 30 | 8.2 sec. (0 to 20) |
Props | 31x40x5 Veem |
Load | 3 persons, 1/2 fuel, 1/4 water, 50 lbs. of gear |
Climate | 81 deg., 70 humid; wind: 10-15 mph; seas: 1 |
Engine Options
Tested Engine |
2 x 1,135-hp CAT C18 Acert |
---|---|
Std. Power |
Not Available |
Opt. Power |
Not Available |
Captain's Report
Learn More
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Mission
The 650 Fly is designed to be owner-operated. It is comfortable for extended onboard cruising and stylish for entertaining while providing dependable offshore performance.
Major Features
- Custom carbon-fiber hardtop keeps weight down
- Walk-in engine room
- Midship master suite
- Yacht controller joystick and remote
- Fore and aft thrusters
- Fore and aft thrusters
Comparison
For yachts in this price range, many builders keep the base price low but can overwhelm the buyer with options so extensive that the actual price may be multiples of the base price. The Neptunus 650 is just the opposite, with most items standard.
Performance
The yacht self-checks… when systems are ready for getting underway these annunciator lights at the helm turn green. If any are red, then she’s not ready for engine start or getting underway.
We had a bit of a tight squeeze when departing our slip. The maneuverability of the 650 made it a non-event and highlights how anyone with a bit of experience can handle her without paying a captain for every trip. The combination of the straight shafts, huge props, and 15-hp bow and stern thrusters allowed us to ease her out and around with just a few gentle shots of the controls.
Thrusters are Important. Even after leaving the marina, we had some tight maneuvering to do and it was completely without surprise or tense moments. Additionally, we had several holds for the many bridges we had to wait for. One got a good feel for the strength of the thrusters and how they’re able to not only hold off but push against a stiff crosswind. Again, no tense moments, and no thruster burn out. And we really worked them to make sure.
The owner’s engine upgrade to twin 1136-hp CAT C18 Acert’s turning 31x40x5 Veem propellers through 1.97:1 reduction gears had plenty of power.
Once at our inlet, with open water ahead, it was time to push the C18’s and let her run. We discovered that she’s very responsive to the throttles, coming on plane in an average 6.9 seconds and getting to 20 MPH in 8.2 seconds.
WOT Speed
During our test, the 650 Fly reached a top speed of 30.1 knots in choppy conditions. We compared this to Neptunus’ factory test in calm conditions, they reported a top speed of 31.5 knots. So this just goes to show how sensitive even large yachts are to sea conditions.
Best Cruise. When we backed off to 2000 rpm and 24.1 knots, the 650 showed her best economy with a fuel burn of 95.5 GPH and a range of just under 250 NM, all while still holding back a 10-percent reserve of the boat’s 1100 gal (4163.8L) total fuel capacity.
Handling
At 88,255 lbs. (40,031.7 kg.) the 650 is a relatively heavy boat, but even when turning aggressively, there’s only a gentle 12-degree lean and nothing happens quickly, so everyone onboard will remain comfortable.
Yachts in this class aren’t about hard turns, they’re about going straight and far and doing it in style, and it’s here that she again delivers. We had 1’ (.30m) rollers on our test that slowed us a little but did nothing to show how she handles rough conditions. Finding a stray wake showed her making a smooth penetration with no hull slap, with the bow throwing the water out wide.
We brought the 650 back into the dock using the remote Yacht Controller, rather than the helm station. We were concerned about it losing connectivity or dying in the middle of a maneuver, but this never happened.
One caveat though… always keep the bow of the controller aligned with the bow of the boat. If not, it’s easy to get disoriented and inputs will be opposite of what one wants. That said, we brought the 650 into the tight slip with absolute precision.
Construction
The Neptunus 650 Flybridge carries a CE rating of A-Ocean which covers largely self-sufficient boats designed for extended voyages through winds of more than Beaufort Force 8 (speeds over 40 knots), and significant wave heights above 13’ (3.96 m), but excluding abnormal conditions, such as hurricanes.
All of the stringers for the engine mounts are made from Corecell A500 foam (which has a density that amounts to five lb. per cubic foot), and they are positioned with laser precision – literally. Neptunus uses Corecell A300 throughout the rest of the yacht. They’re all laid in, literally, with laser precision.
Boat Inspection
Aft Deck
With the outdoor grill on the aft deck and three folding deck chairs, a cookout for six people gathered around the table would seem natural. The sea of teak decking aft is a standard feature of the 650 Fly.
A rail running the length of the house sides supplements the side rails that come up 28” (71.12 cm), exceeding safety standards. Side boarding is accommodated by a sliding section of rail amidships. Fully forward the rail height increases to 38” (96.52cm).
Bow
Ground Tackle
The 200’ of chain rode leads over a polished anchor roller supporting a gleaming plow style anchor. For safety’s sake, a chain stopper takes the standing load off the windlass. To the sides are foot control switches, and further outboard are two 14” (35.56 cm) cleats.
Flybridge
Flybridge Helm
The compass is just below and in line with the steering wheel, which is mounted to a fixed base. We’d like to see a wheel with more rounded spokes that aren’t as hard on the fingers when spinning the wheel, but most of the piloting will be done by autopilot or the Yacht Controller.
More of the leatherette material is on the lower dash, below which are the VHF, the Fusion stereo, the electrical switches and another set of annunciator lights for the vessel’s self-check system. To the right of the wheel are two round fuel gauges flanking more electrical switches.
A great feature - bilge pump counters, resettable to zero, that track the amount of water pumped. Above is the yacht controller joystick, the bow and stern thruster controllers, trim tabs, and the SeaKeeper gyro control screen.
This is an important detail as wipers don’t work on isinglass and looking through it in the rain is problematic. This single detail makes the fly-only bridge work. The isinglass panels on the centerline can open to allow air to flow through.
To the port side of the helm is a lounger with a back that adjusts into multiple positions, both forward, and aft facing.
Overhead, a custom made carbon fiber hardtop adds protection from the sun. The top is supported by heavy-duty stanchions and includes lighting, speakers, and opening hatches.
Salon
The salon of the 650 Fly is a comfortable seating area for six adults. Its’ open atmosphere comes from the high 6’8" (2.03m) ceiling upholstered in Ultraleather and surrounding windows trimmed in high-gloss cherry. Solid wood flooring is standard.
Galley
The galley of the Neptunus 650 Fly follows an American-style kitchen with full-sized appliances and a center island.
Jenn-Air refrigerator and freezer drawers are just forward of the full-size oven, with a four-burner induction cooktop just above. A convection microwave is in the overhead cabinetry. More opening windows are provided to this side. The stainless sink is corner mounted.
Lower Decks
Master Stateroom
The decorative element found in the salon is repeated in the master suite above the nightstands to both sides of the bed. Light from the large hull-side windows with integrated opening portlights plays on the matching grain cherry chests of drawers to port and starboard.
Accent lighting under the drawer sets falls on the wall to wall floor covering.
Ensuite
VIP Stateroom
The same headboard treatments from the master are repeated here. Storage is over the portlights, under the berth, and in the full-length hanging lockers.
On the aft bulkhead, there’s a 24" (61 cm) TV and just below is a convenient shelf where there would otherwise be wasted space. Headroom here is 6’9” (2.06 m) which leaves 3’7” (1.09 m) above the berth.
VIP Head
Just to port of the entry is the door to the ensuite head.
Third Stateroom
Crew Accommodations
Engine Room
Everything is well-labeled, all hoses are double-clamped, and all components are electrically bonded. There are six bilge pumps onboard with two in this compartment.
On the port engine room bulkhead, starting aft is the control for the seven-ton chilled water Dometic air conditioning system. If amperage from shore power is insufficient, one can change the capacity of the chiller, dropping from seven tons to four to accommodate going from 24,000 to 12,000 BTUs.
Safety is well thought out. In the event of a fire, the air dampers to the Delta T air filtration system to close off the air supply, the fire suppression system discharges, and the electronic fuel valves close off. The well-laid-out engine room demonstrates that ease of use was a priority for Neptunus.
Optional Equipment to Consider
- Upgrade to Cat C18s 1136 HP – $50,000
- Custom flybridge hardtop – $46,700
- ¾ flybridge enclosure – $24,500
- Dual 16,000 BTU AC on fly – $31,000
- SeaKeeper 9 – $95,000
Observations
The Neptunus 650 Fly is every bit the cruising yacht she was intended to be. She’s got a comfort level and the performance that match her style.
We like having a single helm on the flying bridge as it frees up room on the main deck. However, making the canvas and isinglass tight is important, as are the tempered glass windshields. With climate control on the flying bridge, there is no reason why this yacht can’t be used in most seasons. Eliminating a heavy hardtop or fiberglass enclosure keeps the CG lower. In addition to her CE Category A Ocean certification, this boat is also ABYC certified.