The 2013 MetalCloak ULTRA4 Nor-Cal Stampede brought full-size rock-racing machines to Prairie City SVRA near Rancho Cordova, California. During a break before Saturday’s main event, Dave Eulberg gave the crowd a different kind of demonstration by taking his modified Polaris RZR XP 900 onto the ULTRA4 course for two laps.
The Stampede featured a $10,000 purse and qualifying positions for the 2014 King of the Hammers. The top 10 finishers earned invitations to compete in Johnson Valley, California. Learn more about the event’s UTV roots in our history of the King of the Hammers UTV race.
A Long-Travel RZR XP 900 on the ULTRA4 Course
Eulberg’s RZR XP 900 was equipped with an HCR Racing long-travel suspension system, 30-inch STI Roctane XD tires and 14-inch STI beadlock wheels. Although it was a demonstration rather than a race entry, he did not hold back when he reached the course’s rock jump.
The demonstration offered a memorable comparison between a recreational sport UTV and the purpose-built 4400-class machines normally associated with ULTRA4 racing. The RZR’s long-travel suspension, larger radial tires and beadlock wheels helped it negotiate terrain far more severe than a stock XP 900 was designed to tackle.
STI Roctane XD Tires
Eulberg’s RZR was running 30-inch STI Roctane XD radial tires. The Roctane XD used a non-directional tread pattern, wide footprint and reinforced RocWall sidewall construction intended to improve durability and stability in rocky terrain. Its deep rim guard also helped protect the beadlock wheel when navigating rocks.
Read our original coverage of the STI Roctane XD tire launch for a closer look at the tire’s construction and intended applications.
HCR Racing Long-Travel Suspension
The HCR Racing system fitted to the XP 900 featured high-clearance boxed front A-arms, boxed arched radius rods and King 2.5-inch reservoir shocks. The setup increased suspension travel to more than 17 inches, stretched the wheelbase by four inches and widened the RZR to approximately 70 inches.
Those changes transformed the stance and capability of the early RZR XP platform, providing additional ground clearance, wheel travel and stability for the Stampede’s rocks and jumps. Visit HCR Racing for its current UTV suspension offerings.
UTV Racing at Prairie City SVRA
Prairie City SVRA was also home to the Nor Cal Rock Racing series, which offered dedicated UTV competition alongside 4400, 4500–4600, Sportsman and street-legal classes. Its regular UTV courses avoided some of the largest obstacles found on the Stampede layout, making them more accessible to side-by-side racers.
We have spent considerable time testing UTVs at Prairie City over the years, including an early Can-Am Maverick tire test at Prairie City SVRA.
More from the event: View the original MetalCloak ULTRA4 Nor-Cal Stampede photo gallery on Facebook.
