Reviewing The Yamaha 21-Series Sportboat: More Speed, Less Sound

Yamaha 21-Series Sportboat

More power, quieter operation, and the precise handling of the Yamaha Articulating Keel significantly upgrades the third-generation Yamaha 21-foot sportboat range.

Yamaha has revealed an all-new 21-foot sportboat platform that will support five distinct models, each faster, quieter, and loaded with more features than the best-selling boats they replace. This third-generation 21-foot Yamaha hull boat line measures 21’3” LOA over a beam of 8’6”, dimensions that have not changed since the first SX 210 was launched in 2006. The new boat does have new lines; a more sweeping bond line highlights the distinctive Yamaha transom design and a broader bow creates more seating area forward. The new boats also feature technology that trickles down from Yamaha’s 24-foot models like the AR240 introduced in 2015, including a significant effort towards sound suppression and the Yamaha Articulating Keel system for improved handling. Let’s take a quick look at the 212X, a version designed for wake sports.


Yamaha successfully addresses the irritating noise issue that had afflicted previous models with a comprehensive package of updates. Those include thicker sound insulation in the engine hatch and deck, improved isolation of the engine bay from the cockpit, and changes to the exhaust system. One of the sources of noise in any jet boat is the flow of water through the pump, which is mounted within the hull. Yamaha has changed the shape of the pump inlet in the bottom of this new 21’ hull to minimize turbulent water flow, and also changed the design and hardness of the rubber coupling between the pump and the engine and the engine mounts. Combined, these efforts reduce the sound level from about 90 dB-A to about 85 dB-A at cruising speeds, measured at the helm. At 30 MPH engine RPM is about 6500, quite a bit higher than a sterndrive or an outboard at the same speed. The engine sound produced by the new Yamaha boats is still at a higher frequency, which the human ear does not always appreciate. However, a decrease of 5 dB-A is a huge difference (the scale is logarithmic) and addresses the one issue we’ve had with Yamaha boats over the years.

The articulating keel (Yamaha does not call it a rudder) debuted on 24-foot Yamaha boats two years ago, is now featured on the 21’ boats, and includes a dihedral keel fin that’s about six inches deep at the transom and extends forward beyond amidships. A cast-aluminum, articulating extension at the transom adds perhaps another 12” to the length of the keel and is hinged and steered via a tie-bar that’s connected to the starboard jet pump nozzle. This rudder-like articulated keel doesn’t project below the hull and so maintains the boat’s minimal draft, a feature of jet power. It greatly improves tracking at no-wake speeds; addressing the annoying wander that has always been an issue on rudderless jet-powered boats.



Compact and light-weight Yamaha TR-1 engines fit with room to spare and deliver improved mid-range power.


The new Yamaha SX210 and AR210 models are the first sport boats powered by the Yamaha TR-1 High Output engine, in this case a pair of the 1.0-liter, three-cylinder power plants each good for about 130 HP at a peak 7800 RPM. In the 210-series boats, the TR-1 engines replace the MR-1 engines that have been around for more than a decade and had to rev to 10,000 RPM to make 110 HP. The reduction in engine RPM makes a big contribution to the quieter operation of the new boats. The TR-1 engines are 40 percent smaller dimensionally and 20 percent lighter (about 30 lbs.) than the MR-1, while making more power on less fuel. The compact TR-1 engines will also be much easier to maintain because service points, like the oil filter, are handy and there’s so much room around the engines. The up-scale 212-Series models are powered by twin 1.8-liter four-cylinder Yamaha engines rated at about 180 HP each.



The new 210-series features a broad bow for more room forward. This AR210 model comes with a sport tower. The can speakers are an option.

Both of these models feature wrap-around seating in the cockpit with hinged bottom cushions port and starboard covering deep stowage compartments. The battery and battery switch are located below the port seat under a rigid cover and will be very easy to service. The area under the seat near the port console is open and you could slide a cooler or gear under it. The port console can also be used for stowage and will hold a boat cover, lines and fenders, and the snack table. There’s also stowage in the helm console. An important new feature at the helm is the Yamaha Connext 4.3-inch touch screen display that incorporates a depth finder, fuel gauge, speedometer and tachometer, compass heading and fuel use data (and was called out as an important advancement, in our Top 5 Powerboat Design Trends article). At anchor the display monitors voltage and water depth, and sounds an alarm if battery voltage goes low. The control for a four-speaker Infinity Marine audio system with Bluetooth and AUX input is also at the helm, and these boats are equipped with the Yamaha Cruise Assist/No Wake Mode speed control system. A highlight in the roomy bow is a new platform that covers a boarding ladder and an anchor cradle–note that you can access the anchor without touching the ladder. The signature Yamaha bi-level transom design is refined with grooved Hydroturf mats on both levels, padded backrests, a table mount, and wet stowage over the pump clean-out ports. The SX210 ($39,999) comes with a Bimini top, snap-in carpet, the table and a tandem-axle trailer with disc brakes. The AR210 ($42,499) adds a forward-sweeping tow arch with integrated Bimini top and a wide-angle rear-view mirror.

We ran the AR210 at the media intro and were impressed with the new TR-1 engines, which offer much more mid-range power than the MR-1 and help the boat hold plane in turns. The boat is happiest cruising between 6500 and 7000 RPM, a narrow range but a good speed for getting around the lake. The AR210 planes with no bow rise, and went from zero to 30 MPH in just seven seconds. The articulated keel seems effective in this boat, as it tracked well in cross-winds and chop. The boat is much quieter than previous Yamaha 21-foot models, but still not as quiet as the outboard-powered runabouts we’ve been testing recently. 



The articulating keel on the 21’ Yamaha watercraft, including this 212 Limited S, also improves handling and tracking at higher speeds and when towing water-sports toys.

The new 212 models utilize the same hull and deck as the 210 models but offer the more-powerful engines and a more luxurious interior–the upholstery is more complex, the deck is covered with teak-look soft mats, there are twin reclining bucket seats at the consoles, and grab handles are billet aluminum. There’s a deep lockable glove box at the port console and a six-speaker audio system includes a pair of speakers on the transom platform. The helm includes the full-feature Connext system with a seven inch touch screen and joystick that can be used to manage audio functions.

We spent an afternoon playing with the 212X, an outing that included some (attempted) wake surfing–another benefit of jet power is that all of these boats are safe for surfing. The ballast system includes rigid tanks aft port and starboard and a soft ballast bag in the ski locker space. The Connext screen controls the ballast system, with separate fill-drain functions and gauges for each tank and six programmable pre-sets. This boat’s tower is dressed up with some billet accents and comes with pivoting board racks that can hold a surf board. Top speed with the tanks drained is about 51 MPH, and with 360 HP under the hatch, the 212X accelerates even harder than the 210. We had fun trying to surf with this boat, but the wake is not very big, the sweet spot is pretty small, and the jet outlets leave a froth behind the boat.