The Polaris RZR Pro R Boost Ultra has plenty of power—but how does it behave when the trail calls for slow, precise movement? Our own Justin Kee joined UTV Guide at Sand Hollow to find out, putting a customer’s new Boost Ultra through the rocks on Milt’s Mile.
The outing focused on low-range performance, clutch engagement and throttle control. Justin’s takeaway was encouraging: the turbocharged Boost retained the low-speed manners he appreciates in the Pro R.
Planning your own trip? Check out our Sand Hollow UTV prep checklist before heading out.
Watch the Boost Ultra in the Rocks
Watch Justin tackle Milt’s Mile in UTV Guide’s rock-crawling video, and read the full Pro R Boost Ultra review for the detailed test findings.
Manageable Power in Slippery Conditions
Recent rain left water, mud and slippery sandstone along the trail. The customer’s Boost Ultra was running stock 32-inch BFGoodrich KM3 tires at 10 PSI, which Justin felt was more pressure than ideal for those conditions.
Grip became the main limitation. The outing didn’t reveal a low-range gearing problem, and Justin didn’t identify clutch engagement as a drawback. Instead, he highlighted how easily he could control the power:
“It crawled good. The power was very manageable.”
That’s encouraging feedback for drivers wondering how the Boost’s additional horsepower translates to technical trail driving. The wet conditions limited the test, though, and another outing on dry rock would help establish more about its capability.
The Ultra’s Suspension Adds to the Package
The Ultra’s DYNAMIX DVS system includes SDi-developed active sway bar links, allowing the suspension to adapt its sway bar connection as conditions change.
UTV Guide previously tested that technology with Justin in a naturally aspirated Pro R Ultra. That earlier machine had larger sticky tires and other upgrades, so it isn’t a direct traction comparison with this Boost on stock tires. This outing’s strongest takeaway was the Boost’s manageable low-speed behavior.
Coming Next: A Full UTV Pros Build
This customer’s Boost Ultra has more ahead of it. We’ll be doing a full build here at UTV Pros, including a cage and full suspension from Geiser Performance.
Getting time behind the wheel before the build gives Justin a useful starting point. Stay tuned as we share the upgrades and follow this Boost Ultra into its next chapter.
For another look at how we build and test a Pro R, see Michael Lee’s King of the Hammers Pro R build, including its first Sand Hollow shakedown.