Government shutdown or not, we needed some sand therapy. In October 2013, we loaded four Polaris RZRs and headed to Sand Mountain Recreation Area in Nevada. The trip gave us a chance to dial in our turbocharged Jagged X RZR XP 900 and test a new set of GMZ Sand Stripper tires on the then-new Polaris RZR XP 1000.
A Government Shutdown Complicates the Trip
I was in serious need of some sand therapy and convinced my friends that a quick midweek trip to Sand Mountain, Nevada, was in order. We picked a random Tuesday and expected the dunes to be nearly deserted, but this was no ordinary October.
The federal government shutdown was in full swing and had closed more public facilities than I had anticipated. I expected national museums in Washington, D.C., to be affected, but Bureau of Land Management and Forest Service recreation areas had not really crossed my mind. That changed when friends in Oregon reported that the Oregon Dunes National Recreation Area had been closed by the Forest Service.
We then heard that the BLM’s Carson City office had technically closed Sand Mountain but might not enforce the closure. No one answered the phone at the BLM office, so committing to the four-hour drive from the Sacramento area involved some risk.
We decided it was worth taking the chance and loaded four RZRs for the trip. I brought our Polaris RZR XP 1000 with a fresh set of GMZ Race Products sand tires, along with our big-bore, turbocharged Jagged X RZR XP 900. My friend Jeff brought his new XP 1000, while John hauled his proven XP 900.
We arrived before 10 a.m. and were relieved to see several camps already set up and ATVs running around the flats. It was far from crowded, but seeing other riders confirmed that we would get our day in the dunes.
Dialing In the Turbo Jagged X RZR XP 900
Our first job after unloading was to check and adjust the Attitude Industries EFI controller on the Jagged X RZR. I had been too busy during DuneFest to properly tune the car on its first outing, so we needed to verify that it was receiving enough fuel for its combination of a Muzzys 995cc big-bore engine, K&T Performance/Race Proven Motors turbo system and K&T cylinder-head work.
My friend Paul Hart climbed into the passenger seat while we made several passes across the flats, progressively working through the RPM range and monitoring the air/fuel ratio. After a few quick adjustments, we made a half-speed run toward the top of the mountain and followed it with several increasingly aggressive passes.
The tuning process only took about 15 minutes, but it gave me confidence that we would not hurt the engine while running at full throttle in the dunes.
I then handed the driver’s seat to Paul and stepped out to take photos. The power delivery was strong and smooth. We ran in two-wheel drive throughout the day, and the Sand Tires Unlimited tires supplied by Fullerton Sand Sports worked perfectly. The RZR had enough power to climb anywhere we wanted in 2WD, which also allowed the rear end to drift more freely. The STU tires were mounted on 14-inch HiPer dual-beadlock wheels.
The car performed extremely well for the rest of the day. Its long wheelbase, Jagged X long-travel suspension and FOX 2.5-inch shocks made it feel more like a small sand car than a traditional UTV. The turbocharger and big-bore engine supplied the power to match.
SDR Motorsports also did an outstanding job with the roll cage, doors, bumper and turnkey installation. A custom graphics package designed by 4130 Clothing helped the RZR stand apart from everything else in the dunes.
Learn more about the complete Polaris RZR XP H.O. Jagged X Edition build.
Testing GMZ Sand Strippers on the RZR XP 1000
We also brought our Polaris RZR XP 1000. TMW Off-Road had installed a roll cage and doors at the Sand Sports Super Show, while Wolf Designs created a custom wrap. I had also replaced the factory radius rods with a high-clearance setup from Long Travel Industries and upgraded the shocks with a package from Walker Evans Racing.
The newest additions were a set of GMZ Sand Stripper tires mounted on Venomous wheels. The wheel offset made the XP 1000 approximately five inches wider than stock, providing additional stability in the dunes.
The six-ply radial tire combination consisted of 28×12-14 three-rib Sand Stripper steering tires up front and 28×15-14 Sand Stripper HP paddles at the rear. The HP version was designed for higher-powered machines and featured 14 full-length paddles measuring approximately 1 1/8 inches tall.
At Sand Mountain’s roughly 4,500-foot elevation, the HP rear tires proved slightly too aggressive for a stock XP 1000. They worked well, but the additional paddle load pulled the engine down to approximately 7,500 rpm while climbing the mountain’s steep face. A less aggressive paddle or additional engine power would have been a better match for these conditions.
We expected the combination to work better on our RZR XP 4 1000 at Glamis, where the elevation is close to sea level and the sand is finer. Read more about the original GMZ Sand Stripper dune-tire lineup.
Our XP 1000 was being developed as a dual-purpose machine capable of both dune riding and rock crawling. The complete evolution of the vehicle is documented in our Polaris RZR XP 1000 build.
Four RZRs and an Empty Mountain
Jeff’s new XP 1000 was equipped with 30×10R14 Maxxis Bighorn tires mounted on STI beadlock wheels. He was able to reach every part of the mountain without difficulty. John brought the XP 900 he had previously used at the King of the Hammers.
We all had a great time. Sand Mountain was accessible, the weather was ideal and every UTV ran without a problem. What began as an uncertain four-hour drive turned into exactly the midweek dune escape we needed.
More Photos from Sand Mountain
