Josh Starrett's Open Mod class Polaris RZR was purpose built for winning at the highest level of UTV cross-country racing. There aren't too many people who can drive a side-by-side between trees faster than Kentucky's Starrett; having already won a championship in the GNCC Lites Modified class (2008), he's moved to the Open Mod class in 2010 with hopes of proving that he just might be the best UTV racer on the East Coast.
Building a fast yet reliable machine was the priority for Starrett, and having created a few impressive Polaris RZRs ourselves, we were simultaneously curious to see what his approach might be and more than willing to share our knowledge of all things RZR. As luck would have it, we were already in the process of putting the finishing touches on part two of our own GNCC RZR build. Luckily, Starrett didn't need much help, and what he came up with on his own is brilliant in its simplicity, performance and design.
Finding the right balance between speed and reliability is always a challenge; to strike that balance Starrett went to longtime sponsor Trinity Racing. Being that the GNCC races are pretty long and the courses are tight, adequate speed could be easily achieved with no more than Trinity's Stage IV exhaust and EFI controller. The Stage IV exhaust is sleek, lightweight, has trick anodizing options and even boasts a lifetime warranty. The EFI controller's installed maps are more heavily guarded than Bin Laden's whereabouts, and according to Trinity, they're the industry's best. While seemingly light in the mod department, everyone involved agreed that for longevity's sake, it would be the safest route and the combo should be plenty for the tight confines of the East Coast's woods courses. In the unlikely event that Josh feels outmotored, he can either remap or opt for a Trinity Pro-Port porting job. Airflow to the motor is handled by a K&N stock replacement filter wrapped in an Outerwear's pre-filter.
Effectively getting the power to the ground is imperative, and for this Josh opted for the Maxxis Razr 4-Speed tires. The 4-Speed's radial construction and lightweight design provide great traction and bump absorption in pretty much all conditions. The conditions at GNCC races are usually rough but rarely excessively muddy, which makes deeper lugged tires unnecessary. The 4-Speed's aggressive tread pattern is based on Maxxis' Razr ATV tire, and the tires' light weight really reduces the effort required for steering.
With weight savings as a top priority, the 4-Speeds are wrapped around a set of HiPer Technology's new 12-inch Tech 3 wheels. Outside of just plain looking cool, the Tech 3s are HiPer's strongest wheel and are a three-piece, modular design, with two carbon fiber halves and an aluminum center section.
In order to increase reliability and traction, all four wheels on the RZR are fitted with TireBalls. Made from state-of-the-art materials TireBalls are 10 times more puncture-resistant than conventional neoprene tubes. In woods racing, you really never know what lies around the next corner, and with the high frequency of bottlenecks due to the width of UTVs, you're often literally forging your own trail around the main trail, making flat tires that much more likely. While punctures are still possible with TireBalls, they're very rare, and instead of losing all the air in your tire, only one cell goes flat, which keeps you in the race and in Starrett's case the championship hunt. Outside of the flat prevention, TireBalls have an equally advantageous quality: They improve traction by allowing you to run a lower air pressure, thus increasing the tire's contact patch.
The end result is a nimble, quick-handling machine with enough bite to get through the rough stuff, enough side bite to handle the slick stuff, and enough lugs to put the power to the ground.