UTV of the Month — January 2011
The original Polaris RZR changed expectations for a recreational side-by-side, but the introduction of the 2011 Polaris RZR XP 900 pushed the sport UTV category much further. With 88 horsepower, a 64-inch stance, a longer wheelbase and an all-new trailing-arm rear suspension, the XP 900 arrived ready for high-speed desert and dune riding.
Polaris already offered UTVs for work, recreation and trail riding, but the RZR XP 900 represented a more focused approach to performance. It was not simply a more powerful version of the original RZR. Its engine, transmission, chassis and suspension were engineered as a complete high-performance platform.
Those changes made the 2011 Polaris RZR XP 900 an easy choice for UTV of the Month in January 2011—and an important model in the broader history of the Polaris RZR.
Long-Travel Suspension Built for Rough Terrain
The 2011 RZR XP 900 delivered 13.5 inches of front suspension travel and 14 inches at the rear. At the time, those numbers placed it well ahead of most production sport UTVs. The Polaris RZR S was one of the few machines that came close, while the Can-Am Commander and Arctic Cat Prowler offered approximately 10 inches of travel. The Yamaha Rhino and Kawasaki Teryx had less than eight inches.
Travel numbers were only part of the story. Polaris equipped the XP 900 with FOX Podium X 2.0 piggyback reservoir shocks featuring adjustable spring preload and compression damping. This gave owners more control over suspension setup for different terrain, payloads and driving styles.
The biggest change was the new three-link trailing-arm independent rear suspension. Two long radius rods extended forward beneath the seats, helping the rear wheels move through their travel with minimal unwanted geometry changes. The design improved stability and control through whoops, chop and other rough terrain, particularly at higher speeds.
Longer Wheelbase in a Compact Package
Wheelbase has a major influence on how a UTV behaves through rough terrain. A short-wheelbase vehicle can feel busy or unsettled when crossing a series of whoops, even when it has enough power to maintain higher speeds.
Many competing sport and recreational UTVs of the era had wheelbases in the 75- to 76-inch range. The RZR XP 900 stretched that measurement to 81.4 inches. The additional length between the axles helped the chassis remain more composed through high-speed desert terrain.
What made the packaging especially impressive was that Polaris achieved the longer wheelbase without creating an excessively long vehicle. Despite having more distance between its axles, the XP 900 was approximately seven to 10 inches shorter overall than several competing sport UTVs. That combination delivered high-speed stability while retaining relatively compact dimensions.
88-Horsepower ProStar 900 Engine
The XP 900 introduced Polaris’ 875cc ProStar 900 twin-cylinder engine. Although its displacement was smaller than the 976cc engine in the Can-Am Commander 1000, Polaris advertised 88 horsepower compared with 85 horsepower for the Commander.
The XP 900 also carried less weight. With a claimed dry weight of 1,190 pounds, it had a power-to-weight ratio of approximately 13.5 pounds per horsepower. Using the period figures of 85 horsepower and 1,287 pounds for the Commander produced a ratio of approximately 15.1 pounds per horsepower.
That difference helped the XP 900 deliver the hard acceleration that immediately distinguished it from earlier production sport UTVs. At a time when most naturally aspirated side-by-sides produced substantially less power, 88 horsepower in a relatively light chassis was a major step forward.
Low Center of Gravity
Like the earlier RZR models, the XP 900 positioned its engine behind the seats. This layout allowed the driver and passenger to sit lower in the chassis than they could in many utility-based side-by-sides.
The lower seating position helped reduce the vehicle’s center of gravity, improving cornering confidence and making the XP 900 feel more like a purpose-built sport machine than a modified utility UTV. Combined with its wide stance and suspension travel, the layout contributed to the planted handling that became one of the RZR XP’s defining characteristics.
64-Inch Width for Stability
The 2011 RZR XP 900 measured 64 inches wide. That made it four inches wider than the RZR S and more than nine inches wider than a Yamaha Rhino.
The wider stance increased stability during aggressive cornering, dune riding and rock crawling. It also gave Polaris room to engineer the long-travel suspension without relying on aftermarket components.
The tradeoff was trail access. At 64 inches wide, the XP 900 was not intended for width-restricted 50-inch trails. Polaris continued to offer the original 50-inch RZR for narrow routes while positioning the XP 900 for open desert, dunes and wider recreational trails.
2011 Polaris RZR XP 900 Key Specifications
- 875cc ProStar 900 twin-cylinder engine
- Electronic fuel injection
- 88 advertised horsepower
- Dual overhead camshafts
- Four valves per cylinder
- 180-degree crankshaft
- 64-inch vehicle width
- 81.4-inch wheelbase
- 13.5 inches of front suspension travel
- 14 inches of rear suspension travel
- Three-link trailing-arm independent rear suspension
- 13 inches of ground clearance
- FOX Podium X 2.0 piggyback reservoir shocks
- 1,190-pound claimed dry weight
Purpose-Built ProStar Powertrain
The ProStar 900 was developed specifically for high-performance side-by-side use. Its dual overhead camshafts, four valves per cylinder and 180-degree crankshaft were designed to provide quick throttle response, strong acceleration and balanced operation.
Polaris also developed a lightweight and compact transmission for the XP 900. The drivetrain eliminated right-angle drives on the route to the rear axle, reducing friction and allowing more engine power to reach the rear wheels. The simplified layout also helped reduce drivetrain noise.
Other notable components included dual 46mm throttle bodies, a 750-watt stator and a dry-sump lubrication system. Together, these details showed that the XP 900 was more than an existing RZR fitted with a larger engine—it was an integrated performance package.
More 2011 Polaris RZR XP 900 Photos
Polaris RZR XP 900 White Lightning Limited Edition
ProStar 900 Engine Details
Why the RZR XP 900 Mattered
The 2011 Polaris RZR XP 900 combined power, suspension travel, wheelbase and vehicle width in a way that production sport UTVs had not previously offered. Its 88-horsepower ProStar engine delivered the acceleration enthusiasts wanted, while its trailing-arm suspension and longer wheelbase gave it the chassis capability to use that power in rough terrain.
Later sport UTVs would become wider, faster and more sophisticated, but the XP 900 established the basic formula that continues to define the category: substantial horsepower, long-travel suspension, a low seating position and a chassis designed specifically for aggressive recreational driving.
For more background on the models that led to the XP 900—and the machines that followed it—read our complete Polaris RZR history.
