If ever there were a boy racer snowmobile, the 2015 Arctic Cat ZR 4000 RR is it. That little green monster was built by Arctic Cat to get young riders on cross-country and snocross racetracks.
SG staffers aren’t racers. And judging by the fact that popular music from when we were in high school is now played on classic rock radio stations, we definitely aren’t kids either, but we made a 2015 ZR 4000 RR one of our demos anyway because it was an exciting, all-new model that we thought might be fun for whipping up and down the trails and ditches.
With “Team Arctic” emblazoned on the side panel, it featured a certain roguish appeal with a notably louder exhaust sound than our other demo models. It’s powered by the non-power valve, 499cc, liquid-cooled Suzuki twin that debuted in the 2004 Arctic Cat Sabercat. Cylinders for the 85 hp, fuel-injected engine are fed by a 38mm throttle body. It’s been a durable two-stroke engine that most recently powered the Sno Pro 500 racer, a model that the ZR 4000 RR replaced.
The ZR 4000 RR includes a set of premium Fox shocks that provides a mind-numbing amount of external adjustability. Ski shocks are FLOAT Evol RC dampers with rebound and compression clickers, plus two separate air-spring chambers so riders can separately set ride height and control bottom-out resistance. The center shock is a Zero 1.5 C coil-over damper with compression adjustment, and the rear damper is a larger diameter Zero 2.0 RC shock with rebound and compression adjustability. Purchased separately, this shock package would cost almost $3,000.
To suit a 155-pound rider, we set the ski shock compression and rebound clickers at five clicks out from full soft and filled the Evol and main chamber air chambers to 120 and 55 psi, respectively. We set center shock compression damping to five clicks out from full soft and also set the rear shock’s compression and rebound clickers to five out from full soft. Torsion springs were on the lowest setting and the coupler blocks were on the second position.
We made those initial settings because experience has shown that a comfortable ride and control usually comes from setting a suspension so it can actually compress. That got us into the neighborhood, but we settled with the ski shocks at four clicks out from full soft for compression and three for rebound, and 130 and 50 psi for the air chambers. Center shock compression went up to six clicks out from full soft because it lightly bottomed at five clicks, and rear shock compression went to two clicks out from full soft and rebound went to one.
As the notes below show, we rode the sled only 400 miles so our experience with the complex shock package was less than we’d hoped for, but hopefully the tuning information provides a baseline for riders who have an Arctic Cat ZR 4000 RR or want to understand suspension tuning. We wanted to log more miles on our demo and run it through varied trail conditions, but limited snow cover in the Midwest during the 2014-15 winter resulted in fewer rides, so the ZR took a back seat to product testing and other machine evaluations.
The engine was responsive and made the sled quickly accelerate from corner to corner, and that made it a fun rig to run through the woods – for some people. During one particular ride in northern Wisconsin, one staffer was enjoying the machine by leaning into turns and wringing every cubic centimeter out of the small-bore engine. His mission was to try to run away from friends on 800s.
During a break, a buddy in the group asked to take a crack at riding it. “You looked like you were having a lot of fun on it,” he said. At the next stop, that friend shook his head and called the RR an untamed beast with too many rough edges, too much engine noise and it took too much work in the turns. “Get me away from this thing,” he said.
As the late baseball legend Yogi Berra allegedly said, “Different strokes for different people.”
2015 Arctic Cat ZR 4000 RR
Modifications: Sled Solutions Elevation Tunnel Bag; Arctic Cat LXR-smoke mid-height windshield
Miles ridden: 402
Weight: 552 pounds, trail ready with full gas and oil tanks, spare belt, tunnel bag and mid-height windshield
Average MPG: 11.93
Average miles per qt. of oil: 108
PIN IT: With half as much power, riders can hold the throttle a little longer than they would on an 800cc twin.
FUN: There’s true appeal to wring out a snowmobile and ride it to its potential.
RUGGED: Though more refined than the Sno Pro 500 it replaces, this model still has rough edges.