Polaris Ace 900 Specs and Review

2016 saw the birth of the Polaris Ace 900 – just two years after the inception of the series. And boy, was it a massive success right off the bat! This hybrid gave many side-by-sides a run for their money, with its long-travel suspension, dual-overhead-cam design, and ridiculous power-to-weight ratio. Moreover, its single-seat design had daredevil enthusiasts wrapped around the machine’s little finger.

The Polaris Ace 900 is a groundbreaking 4×4 produced by Polaris from 2016 to 2019. Sporting a powerful 78-hp EFI ProStar™ engine, plush suspension, 2WD/4WD drive modes, and off-road ergonomics, this four-wheeler gave new life and meaning to high-performance riding.

On the outside, the Polaris Ace 900 looks like a single-seat rock bouncer with its buggy-style roll cage, low-cut doors, and knobby tires. But it is so much more. Read this guide to get to the gist of Polaris Ace 900 reviews and learn more about the American manufacturer’s most powerful – and fun – performance 4×4.

For the Brave and Wild

If one phrase could best describe the Polaris Ace 900, it would be the one above. This four-wheeler is not for the faint-hearted – it has the size of a proper side-by-side but only accommodates a single operator. Riding the machine and letting loose on hardpack and technical trails undeniably takes a tremendous amount of skill plus a lot of bravado.

The Polaris Ace 900 hails from a series of Polaris quads that launched in 2014. Initially released in 325 and 570 displacements, the American firm bumped up the machine in 2016 to 875 cm3 and fitted it with a 60-hp ProStar™ engine. Things got better one year after when the vehicle width increased to 59 inches, the wheelbase grew 6.0 inches longer, and power output upgraded to 78 hp. Also, when the front strut suspension changed to a dual A-arm setup with a redesigned steering knuckle, new tie rods, and Walker Evans racing shocks.

Sport is the name of the game for the Ace; with its central seating position, buggy-like ROPS, and a cockpit spacious enough, it eliminates any difficulty with ingress or egress. Steering action is made quicker with Electric Power Steering, especially when traversing through rocks and ruts or other rough trail sections. Additionally, Variable Assist changes the vehicle’s handling characteristics on the fly, making it less twitchy even at high speeds while enabling it to turn and accelerate on a dime. These highlights, alongside other praiseworthy qualities, make the Polaris Ace 900 an enjoyable yet stable ride.

Polaris Ace 900 Specs & Features

Engine

Like most big-bore Polaris quads and buggies, a four-stroke DOHC twin-cylinder ProStar™ engine brings this four-wheeler to life. Furthermore, it shares the same 93 x 64.4 mm bore-stroke ratio and 10.5:1 compression ratio with the same-class Ranger (The Polaris Ace 900 XC EPS has a compression ratio of 10.6:1). The ProStar® engine fitted into the 2016 Ace SP 900, in particular, is the same 60-hp engine found in the Ranger 900 XP. If you find the Polaris Ace 900 top speed and power output lacking, professional outfitters like HMF Racing can increase horsepower by up to 14 hp with its re-flashed ECU (Just be prepared to spend at least $1,000).

2016 Polaris ACE 900 SP 2017 Polaris ACE 900 XC
Engine Brand Name / Model No. ProStar®
Engine Type 4-stroke, DOHC
Cylinder Arrangement Twin cylinder, 4-valve Twin cylinder, 8-valve
Engine Cooling Liquid cooling Liquid cooling (w/ auto fan)
Carburetion System Electronic Fuel Injection, 42-mm throttle body Electronic Fuel Injection, 46-mm throttle body
Bore x Stroke Ratio 93×64.4 mm
Compression Ratio 10.5:1
Displacement 875 cm³ / 53.4 in³
Engine Fuel Unleaded gasoline of at least PON 87 rating, containing < 5% MTBE (Methyl Tertiary Butyl Ether), < 10% ethanol, or < 5% methanol
Fuel Capacity 19.9 L (5.25 US gal)
Horsepower 60 hp/60.83 PS (44.74 kW) 78 hp/79.11 PS (58.17 kW)
Top Speed 55 – 70 mph (88.5 – 112.7 km/h) 74 mph (119 km/h)
Maximum Speed (If payload > 152 Kg/335 lbs) 43 mph (69 km/h)
Maximum Towing Speed 10 mph (16 km/h) 15 mph (24 km/h)
Air Filtration Large cylindrical paper pleat mesh/screen
Lubrication Wet Sump
Engine Oil & Quantity 2.5 US quarts (2.4 L) of Polaris PS-4 4-Cycle Oil, SAE 5W-50
Transmission 44 oz. (1.3 L) of AGL Gearcase Lubricant & Transmission Fluid
Demand Drive 9 oz. (265 ml) of Demand Drive Fluid 6.75 – 7.6 oz. (200 – 225 ml) of Demand Drive Fluid

Lubrication

Oil capacity is 2.5 US quarts/2.4 liters of SAE 5W-50 PS-4 4-Cycle Oil or its equivalent. It is your prerogative to use any API-certified SJ (or higher) semi/full synthetic oil that meets JASO T903 MA standards and manufacturer specifications. Any other oil variant not meeting these requirements may result in engine damage or render your warranty void.

2016 Polaris Ace 900 SP

Drivetrain

A single-lever shift controls wheel spin, while a dual-range automatic PVT with 4-wheel independent shaft and lockable differential handles power. Selectable driveline modes are available across all trims and models, with a select few having “Turf” mode. Powertrain components provide more than sufficient stability and grip, making it a joy to ride on terrain filled with stumps and craters.

On the downside, its central seating position or center of gravity can prove disadvantageous in certain situations. Unlike ATVs, this 4×4 does not make use of lateral grip to counteract body roll. Hence, you will need to keep pushing the throttle and moving forward to prevent your back-end from hanging out. Also, the Ace has no Active Descent Control or Engine Braking System (EBS) and warrants clutching adjustment for elevations of 1,500 meters or above.

2016 Polaris ACE 900 SP 2017 Polaris ACE 900 XC
Transfer, Transmission Type Dual-range automatic PVT (Polaris Variable Transmission) w/ reverse
Gearshifting Shift-type side lever (H/L/N/R/P)
Drive System Shaft ride system, Close-ratio On-Demand True AWD/2WD
Drive Ratio (F/R) 2.989:1
Gear Ratio Low – 28.84:1
Reverse – 25.83:1
High – 9.65:1
Low – 28.84:1
Reverse – 25.83:1
High – 10.73:1

On-Demand™ True All-Wheel Drive System

This company-exclusive feature turns the Polaris Ace 900 into an unstoppable trail machine. All four wheels automatically engage whenever the system senses wheel spin or loss of traction and changes to 2WD in reverse. Some trims have the VersaTrac Turf Mode switch, which unlocks the rear differential for easier, tighter turns on delicate terrains/surfaces.

Electric Power Steering

Available only for specific trims, this feature includes Variable Assist that makes steering at lower speeds easier. It is mated to the machine’s low-range functions and works best when hauling or traversing rocky terrain. Additionally, it reduces steering wheel feedback and kickbacks from hitting larger obstacles.

2016 Polaris Ace 900 SP ATV

Ignition

Both Polaris Ace 900 XC and SP trims have a digital CDI and electric start system with no recoil starter for backup. The stock spark plug has a gap of 0.028-0.031 inches (0.7-0.8 mm) and may be replaced with Iridium plugs of the same specs. The charging system is a triple-phase alternator (rated output below), supplemented by a 12V, 30 Ah (view on Amazon) sealed or conventional battery. Use a charger like a BatteryMINDer Battery Maintainer (view on Amazon) with an output no larger than 1/10 of the battery’s amperage rating for conventional batteries. For sealed batteries, ensure they are always fully charged and register 12.8V or higher when tested using a voltmeter or multimeter.

2016 Polaris ACE 900 SP 2017 Polaris ACE 900 XC
Ignition Digital CDI (Capacitor Discharge Ignition)
Ignition Timing 10° ± 1° @ 1,200 RPM (non-adjustable)
Spark Plug, Gap MR7F / 0.7 – 0.8 mm (0.028 – 0.031 in) gap; Torque specs: 10 ft-lbs (13.5 Nm)
Alternator Type Triple-phase alternator 
Rated Output 575 W @ 3,000 RPM
Fuse 30 Amp (engine control, EPS); 20 Amp (lights, AWD drive, winch, 12V power receptacle, electronic engine control, starting, fan circuit braker); 10 Amp (fuel pump, EFI, constant vehicle power); 5 Amp (brake)
Battery 12V 30 Ah/(10 Hr), YB30L-B format
Battery Dimensions (L x W x H) 168 x 132 x 176 mm (6.62 x 5.19 x 6.94 in)
Starting System Electric
Instrumentation LCD, speedometer, indicator lamps, Ride Information Center – clock, odometer, trip meter, hour meter, engine temperature, tachometer, programmable service interval, diagnostic display mode, mode button; separate 12V auxiliary DC outlet
Indicator Lamps Over temperature, neutral, high beam (if equipped), helmet/seat belt, check engine, EPS warning, turf mode (if equipped)

Tires & Brakes

Thanks to its tire-and-wheel assembly, uphill climbs is never an issue for either the Polaris Ace 900 SP or XC. Descents, however, are a different story. Because of the absence of EBS, riders will need to focus more on the road if they want to avoid tipping sideways. The good news is that 4-wheel hydraulic discs and parking brakes are efficient in slowing down the machine when needed. Just remember not to slam on the brake pedals during your first 50 stops to ensure the braking system does not get prematurely damaged.

2016 Polaris ACE 900 SP 2017 Polaris ACE 900 XC
Wheel Composition Cast aluminium
Front Tire, off-road/road air pressure AT25 x 8-12, 69 kPa (0.70 kgf/cm2, 10 psi) GBC Dirt Commander AT27 x 9-12, 69 kPa (0.70 kgf/cm2, 10 psi)
Rear Tire, off-road/road air pressure AT25 x 10-12, 69 kPa (0.70 kgf/cm2, 10 psi) GBC Dirt Commander AT27 x 11-12, 97 kPa (0.98 kgf/cm2, 14 psi)
Tread Depth Limit 3 mm (0.11811 in)
Front Rim Size, Offset, Bolt Pattern 12×7, 4+3, 4.156 N/A
Rear Rim Size, Offset, Bolt Pattern N/A N/A
Front Brake Type 4-wheel hydraulic disc (Left foot operation)
Rear Brake Type
Parking Brake, Auxiliary Brake Park in Transmission

Suspension

Suspension on the ’16 Polaris Ace 900 SP was derived from the Sportsman – front MacPherson struts and dual A-arms with coilover shocks. While this setup already made for excellent handling and maneuverability, Polaris saw the need to upgrade the suspension components on the XC model. Instead of coilovers, the ’17 Polaris Ace 900 XC and its later-year versions were equipped with piggyback-reservoir Walker Evans racing shocks (view on Amazon). This change lent to an increase in front and wheel travel by 3.0 inches, as well as more remarkable bottoming resistance and plusher riding experience.

2016 Polaris ACE 900 SP 2017 Polaris ACE 900 XC
Frame Type Steel square tube
Ground Clearance 260 mm (10.25 in) 330 mm (13 in)
Wheelbase 1,562 mm (61.5 in) 1,715 – 1,727 mm (67.5 – 68 in)
Front Suspension Type, Travel MacPherson struts w/ anti-sway bar & dual-rate springs, 208 mm (8.2 in) Dual A-arms w/ stabilizer bar & Walker Evans clicker needle shocks, 312 mm (12.3 in)
Rear Suspension Type, Travel Dual A-arms w/ anti-sway bar & coilovers, 241 mm (9.5 in) Dual A-arms w/ stabilizer bar & Walker Evans clicker needle shocks, 320 mm (12.6 in)
2016 Polaris Ace 900 ATV

Dimensions

The Polaris Ace 900 dimensions range from 2,296 x 1,220 x 1,730 mm to 2,450 x 1,500 x 1,830 mm, depending on year and trim. Its cargo box has overall dimensions of 17 x 35 x 4 inches, although some online sources state the bed height is actually an inch taller. Towing capacity is an impressive 680 Kg (1,500 lbs), and dry weight falls between 392.4 Kg (865 lbs) and 488 Kg (1,075 lbs). The maximum weight capacity (operator, passenger, cargo, and accessories) – is 260 Kg (575 lbs) across all models.

2016 Polaris ACE 900 SP 2017 Polaris ACE 900 XC
Length 2,296 mm (90 in) 2,380 – 2,450 mm (94 – 96.5 in)
Width 1,220 mm (48 in) 1,500 mm (59 in)
Height 1,730 mm (68 in) 1,550 – 1,830 mm (61 – 72 in)
Seat Height (Unloaded) N/A 730 mm (28.75 in)
Dry Weight 392.4 Kg (865 lbs ± 5%) 488 Kg (1,075 lbs ± 5%)
Bed Box (L x W x H) 430 x 890 x 100 mm (17 x 35 x 4 in)
Maximum Weight Capacity 260 Kg (575 lbs)
Carrier Capacity (F/R) 54 Kg (120 lbs) / 108 Kg (240 lbs)
Tongue Weight 68 Kg (150 lbs) w/ 1.25-inch receiver
Towing Capacity 680 Kg (1,500 lbs); 386 Kg (850 lbs) – up to 15°
GVWR 721 Kg (1,590 lbs) 772 Kg (1,701 lbs)
Test GVW – (ROPS) 748.4 Kg (1,650 lbs) per OSHA 29 CFR 1928.53
Colors Stealth Black Matte Silver Pearl, Velocity Blue

Exterior

The Ace’s steel frame encages a roomier cabin from which both riders of all sizes will appreciate. Moreover, it provides the security of a UTV and the aggressiveness of an ATV in one vehicle. The spacious cockpit is further enhanced by the tilt steering wheel and seat sliders. There is plenty of storage under the front rack (3-gallon capacity) and in the dash – not to mention a bed box that perfectly fits additional gear. The instrument dash has cubby holes on each side, provisions for accessory switches, Bluetooth connectivity, and legible icons for the coolant temperature and fuel level.

Comfort is unrivaled on the Ace. But if anything were to change, it has to be the central seat. With the 4×4’s sporty nature, the driver ends up sliding around the seat frequently when in the high of riding. A bucket seat (view on Amazon) would have sturdier harness points and pin the rider in place much better.

2016 Polaris ACE 900 SP 2017 Polaris ACE 900 XC
Standard Features Front brush guard, cab doors, seat belt and latch, fuel gauge
Tool Kit Standard Standard
Switches, Controls Drive mode (AWD), ignition, lights Drive mode (AWD), ignition, lights

Lighting

2016 Polaris ACE 900 SP2017 Polaris ACE 900 XC
HeadlightSingle beam halogen, 12V 55 W x 2Single beam halogen, 12V 55 W x 2
Brake Light/TaillightSingle beam, 12V 27 W/6 W x 2Single beam, 12V 27 W/6 W x 2

Lock & Ride

Synonymous with the Pro-Fit Advantage, this attachment system makes use of a modular cab system offering several accessory options – including windshields and gun scabbards. This accessory integration features dedicated attachment points enabling efficient cab/accessory installation or removal and works well with the purpose-built Polaris Ace chassis.

Polaris Ace 900 Price

Depending on model and trim, the Polaris Ace 900’s list price ranged from $11,499 to $12,999. While they are a bit pricey, the Ace 900 models are still $2,000 less than their competition. The only UTVs slightly cheaper than the Ace are the Yamaha Wolverine 700 ($10,999), the Arctic Cat Prowler 500 ($9499), and the Honda Pioneer 700 ($10,499). But then again, engine displacement and horsepower are considerably lower with these options.

Note that these figures do not cover any accessories outside of the package provided by dealerships. Any performance-enhancing add-ons would cost another $500 to $2,600 on top of the base price. Auction listings and trade-in values, on the other hand, fall between $4,830 and $13,390. These secondhand units are typically in good running condition, with most stock parts still functional and intact. Between the two Ace trims, the 2017-2019 XC models fall on the higher end of the price spectrum.

2018 Product Recall

A select number of Polaris RZR and Ace models sold from 2016 through 2018 have been voluntarily recalled by Polaris due to a faulty fuel pump flange assembly. The composition of the said assembly made it prone to fuel leakage as a result of degraded components. These components, in turn, increase the likelihood of a fire hazard for the wheeler when exposed to an ignition source. Polaris received a total of 21 complaints about cracked fuel pump flange assemblies prior to their announcement of the said product recall. Thankfully, there were no accident or injury reports.

About Polaris

Polaris Inc. is an American company globally renowned for its groundbreaking innovations and class-leading ATVs, snowmobiles, and motorcycles like the Polaris Ace 900 SP and XC models. Having started in the industry by producing farm equipment, the firm has since moved on to different automotive industries. Its Textron acquisition in 1968 has marked the beginning of its expansion program, ultimately resulting in innovations such as On-Demand™ True All-Wheel Drive and Lock & Ride attachment system – to name a few. As of 2019, Polaris has over $6.8 billion annual sales and continues to be a highly-esteemed leader in the Powersports industry.

Conclusion – Polaris Ace 900 Review

Although short-lived, the Polaris Ace 900 embodied pure enjoyment and topped the list of most preferred UTVs for use on technical trails and dirt tracks. It was best in class in sportiness and power and never failed to give enthusiasts one heck of a ride. Polaris may have ceased production of the vehicle, but many of these soloists can still be purchased in various trader and auction sites. Not for the weak of heart, the Polaris Ace 900 will surely test your mettle on the ground.

Kris Peter

Adventure seeker and off-road enthusiast. I love the thrill of going off-road and taking on the elements.

Recent Posts