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.
Engine
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.
Suspension
For woods racing, staying narrow is the top priority, and most aftermarket suspension companies have concentrated on long-travel kits, which are pretty worthless in tight spaces. Luckily, ARS FX is now offering a +2-inch kit, which while slightly wider is still narrow enough for the task at hand. The ARS FX RZR +2 Woods Kit is pretty genius when you think about it; it's a perfect fit for rec riders and woods racers alike, as the arms will work with stock shocks or the Exit X0 or X1 single-rate shock packages. The +2 kit is made from 4130 chrome-moly, which is a good bit stronger than stock, and strength is essential for serious racers. The slight increase in width really does make the stock RZR stance a bit more stable and usable for the average rider, and the fact that it uses the OEM mounting hardware and ball joints helps keep the price lower as well. To further increase strength, Starrett also opted for ARS FX's axle kit, which uses high-strength 300m rear axles and 4340 front axles.
The obvious choice in the shock department was ARS FX's sister company Exit. To sweeten the case for Exit, they're also the brainchild of suspension guru Mike Hallock, and those in the know know that Hallock is at the very top of the Suspension Wizard food chain. The Exit Series X1 UTV shocks have piggyback reservoirs, come standard with HTC springs, are crossover and preload-adjustable and have a dual-rate spring combination in the rear. Since many of us are a bit ignorant when it comes to shock adjustment, Exit has included an external compression adjuster on all X1 shocks, which allows the rider to fine-tune the shock with the simple turn of a knob. The look of the shocks is pretty trick, as all of the aluminum parts are anodized for a durable, long-lasting finish. One of the best features on the Exit package is the Ride Quality Guarantee which states that if for any reason you're not satisfied with the way they are performing, all you need to do is call within the first 30 days of use and Exit will respring and revalve until you are satisfied, at no charge.
Steering, Chassis, Comfort And Looks
With the majority of the mods complete, Starrett turned to his dad/codriver, Charlie Starrett, and the equipment they already own at their business, The Tarp Shop, for some good old-fashioned D.I.Y. modifications. For starters, the duo built a custom roll cage with an integrated radiator mount as well as bumpers comparable to any high-dollar aftermarket company's offerings. "Hell, just about any of the stuff for sale out there is over two grand; I figured Dad and I could just as easily build the stuff ourselves and save a boatload of money," Josh said about the fabrication project. Another project was a lightweight "solid-steering wheel adjuster" which does away with the stock unit and saves a few ounces to boot.
Strengthening the chassis was achieved via a combination of methods, Lonestar Racing's weld-in gusset kit and bolt-in rear main gusset plate were installed, and a series of homemade chassis inserts were added anywhere Josh thought the frame might potentially fail. The frame is fairly bulletproof now, without sacrificing too much in the weight department.
Quickening the steering characteristics is vital to any machine being raced through trees at high speeds. Anything that decreases the time between identifying a potential hazard and the action required to avoid said hazard is a definite plus. With that said, Team Starrett went to Howe Racing Enterprises for one of its revolutionary Stealth HD steering quickeners. The 2:1 ratio Stealth HD uses a patent-pending multiple gear design to increase tooth contact for strength and durability. Unlike other quickeners on the market, the Stealth has input and output shafts that are in line for a reduced gear load. At only two pounds, the Stealth's size is unobtrusive and weight addition is negligible.
A +1-inch steering wheel and quick-release kit which Josh modified for the RZR application was also installed, and outside of looking like something you might find in your granny's Buick, the wheel further increases the steering ratio.
As a safety measure a Holz billet roller cage (made from 7075 billet aluminum) was added. The Holz cage has twice the tensile strength of the competitor's aluminum cages and comes with new springs and rollers preinstalled. The roller cage (Sprague carrier) is hard-coat anodized and is one less part to stress over while racing. Justifying the expense of fixing things that have yet to break is easy for Starrett: "I want this machine to be virtually indestructible, I'd hate for a championship to be blown by a $300 part."
The ability to keep you comfortable during long races is just as important as any other aspect of a good race machine. With that in mind, seating duties were left to PRP's RZR suspension seats. The PRP seats don't just increase comfort, they increase safety by allowing you to sit inside the seat as opposed to on top of it. The seats themselves cradle your body, while the open-bottom design gives you a fully suspended feel. The seats were mated to PRP's 3-inch Competition-style seat belts with padded twin harnesses and crotch straps. The end result is a pretty damn safe-feeling, comfy ride.
As far as looks go, Starrett opted for OEM plastic with a G4 Graphics kit and Outerwears' Shockwears. The look of the machine is a pretty safe reflection of Starrett himself: Kind of clean and corporate, with a touch of class clown thrown in for good measure.
The Ride
As far as how the machine performs, it has netted a win, and a podium in its first two races. It actually performs exactly as it was intended to: nimble, quick and precise. The Trinity mods are enough to get Team Media Allstars' Starrett to the first turn at the front of the pack, the steering and suspension mods soak up the break-neck speeds at which Josh propels the RZR through the woods, and the tires get him where he needs to go without hesitation. Overall, we feel it's a winning package across the board.
ATV Rider 's Media Allstars Woods RZR Part 2
Being that we're in the rare predicament of having two purpose-built woods-racing Polaris RZRs completed at the exact same time, we figured we'd sneak in Part 2 of our original RZR Build (November '08 issue) while we have your attention. I'll keep it quick, but since you last saw our RZR, we've added quite a few mods.
Engine-wise, we've added a Dragonfire ECU. The DFR ECU has added a lot more bottom-end power to the machine and complements the Yoshimura exhaust perfectly. The RZR is now a certified arm snatcher. A couple of changes were made in the tire/wheel department. For starters, we switched from the Maxxis BigHorn to a CST Abuzz, which provides a bit smoother ride, saves a few pounds and has increased side bite. To accommodate the smaller 12-inch tires, we switched to DWT's Diablo beadlocks, which look absolutely amazing.
Chassis-wise, after crushing two stock roll cages we decided to go with Lonestar Racing's roll cage made from 13/4-inch DOM, and it looks really trick. The only big gripe about the cage is it mounts in the stock locations up front but only bolts through the plastic in the bed in the rear, which really doesn't seem very secure. We're in the process of engineering a fix for this. A small gripe is a lack of stock sidebar and net installation locations on the cage. To correct Lonestar's oversight, we installed Pro Armor's Suicide Doors with nets. Every aspect of the Pro Armor doors absolutely rocks; they're by far the coolest part on the new and improved RZR. They function, install easily and give the machine a great look. The aftermarket doors meant we had to switch back to OEM-style Maier plastic with a G4 custom graphics kit. To bulletproof the steering components of the machine a bit more since you last saw it, we installed a set of ARS FX's upgraded stock-width tie-rods and a Trail Armor steering stabilizer. Unfortunately, these two mods didn't exactly play well together, and the Trail Armor stabilizer was eventually bent. In its defense, though, the Pro Armor stabilizer worked fine on the stock tie-rods, and we didn't encounter an issue until we installed the upgraded ARS FX rods (which consequently work great as well).
Build Sheet
Trinity Racing:
www.trinityracing.com; 909/373-1337
Stage IV exhaust system: $599.99;
Polaris RZR EFI controller: $245.99
Exit Shocks:
www.zbrozracing.com; 435/753-7774
Series X1 dual-rate shocks: $2,575 (four shocks)
Maxxis International:
www.maxxis.com; 800/4-MAXXIS
M925 Razr 4-Speed tires, 25x8-12 six-ply front, 25x10-12 six-ply rear
The Tarp Shop:
270/622-7009
+1-in. quick-release steering wheel and adapter kit: $175;
custom roll cage and bumpers and radiator relocation kit: $1,800;
solid-steering wheel adjuster: $30
TireBalls:
www.tireballs.com; 877/847-3225
Kit No. 2103 (25/8/ 12): $199.95;
Kit No. 2102 (25/10/ 12): $199.95
Howe Racing Enterprises:
www.howeracing.com; 989/435-7080
Stealth HD steering quickener (522B2 Stealth 2:1 ratio): $149
Outerwears:
www.outerwears.com; 800/967-3450
Weld-in frame gusset kit: $125;
rear main gusset plate-RZR: $80
HiPer Technology:
www.hiperracingwheels.com; 877/464-4737
Polaris RZR radiator shroud (20-2574): $35.95;
Shockwear, front (30-1158): $31.45
per pair, rear (30-2395): $31.45 per pair;
Pre-Filter for K&N (20-2485-01): $15.95
12-in. Tech 3 wheels: $299 ea.
PRP Seats:
www.prpseats.com; 951/894-5104
RZR suspension seat: $309 ea.;
3-in. Competition-style seat belt: $146 ea.