So you’re not a speed freak needing to be the first rider to the other end of the meadow, but you love the sport of snowmobiling. You also say you’re not an adrenaline junkie who has to try and blow out the top of every hill you come upon, yet riding in the mountains is what you crave the most.
Sounds like you could be in the market for a 2006 Arctic Cat M5 141, Polaris Trail RMK136 or Ski-Doo Summit Fan 136.
The Rodney (Can’t Get No Respect) Dangerfields
Industry insiders refer to these snowmobiles as entry-level sleds. We like to call them the Mountain Sports. The M5 is liquid-cooled while the Trail RMK and Summit Fan are fan-cooled machines. These are the white bread and butter of full-sized snowmobiles, yet come complete with all the basic needs—complemented by some amenities handed down from the top of the line, higher-priced machines, thus enhancing the mountain riding experience.
Some enthusiasts would be bored to tears by just the thought of having to ride a Mountain Sport, yet others would have a hootin’ hollerin’ good time. We always have fun with our time on the 500s and Fans, pounding them to their limits. One thing the SnoWest SnowTest team knows after year upon year of evaluations is that a seasoned boondocker can finesse these little hummers to and fro in some fairly impressive places, especially when you consider their limited resources of power and traction.
We’ve hung some pet names on the Mountain Sport class in the past to the likes of “Little Giants” and “Lightweight Champions.” A befitting pet name for 2006 would be “Mountain Misers,” in respect to the current situation within the petroleum industry.
It’s our bad for not completing our own scientific consumption tests (something to work on next year), so we can only speculate the actual, factual numbers. But age old knowledge tells us that feeding a modest 65 hp fan cooled or a single throttle bodied liquid making 80 hp max is going to consume significantly less fuel and oil in comparison to the 600s that come with larger carburetors or dual throttle bodies and pump out 115 to 120 horses.
If the petroleum dilemma continues to escalate, this miserly 500 and Fans are going to look a lot more attractive from the operating standpoint, not to mention your initial investment in relation to the 600 class. In MSRP, the closest difference is in the $1,700 range between the highest retailing 500 (Arctic Cat M5) and the lowest retailing 600 (Arctic M6 141 and Polaris 600 RMK) and is as much as $2,700 between the lowest retailing 500 (Polaris Trail RMK) and the highest retailing 600 (Ski-Doo Summit 144).
The Arctic Cat M5 has the lone liquid cooled engine of this trio. The Suzuki 499 twin is sporting a new fuel delivery system for ’06—out with the two VM 34 mm carburetors and in with a single 46 mm batteryless fuel injection throttle body. This update didn’t have an impact on horsepower numbers but did improve all around performance, also raising economy numbers (according to Cat personnel). The Suzuki also has a 3D ignition and a guaranteed no more than two pull starting.
Power is transferred from the Arctic rpm sensing drive clutch to the Arctic Roller Cam driven clutch, through the ACT drive system to the 15x141x1.6 Attack 20 track. The afternoons at the new model evaluations were warm and the conditions were subject to sticky, heavy snow at lower elevations. The M5 performed flawlessly all day long in all conditions and elevations—well enough that we couldn’t help but ponder the thought that Arctic is sandbagging the horsepower rating at 80.
The Air Around You
Polaris and Ski-Doo continue to use the original means of cooling for snowmobile engines, that being the surrounding atmosphere (air). Even though these fanners are 550cc motors, they can’t build the horsepower produced by the Suzuki liquid due to engine design coupled with lower peak operating rpm.
The Polaris fan is actually a 544cc twin and is fired by a digital CDI ignition. Intake is 2 VM 34SS carbs detailed with ACCS (eliminating jetting and altitude issues).
The powertrain starts with the Polaris P-85 drive clutch and motivation is delivered to the 15x136x1.25 paddle track via the Team Roller driven clutch.
The Ski-Doo’s power comes from a Rotax 550cc two cylinder that is fueled by 2 VM-34 carburetors and sends its power to the 15x136x1.5 paddle track by means of the Bombardier Lite drive clutch and the Formula R.E.R. driven clutch.
As we rode the Trail RMK and Summit Fan in the higher elevations above Daniels Summit, UT, it didn’t take us long to max out the 65 hp on tap as both have a plate full with their standard tracks. We cut the fanners absolutely no slack as we flogged ‘em … and we flogged ‘em hard.
The 550 fans never skipped a beat, vapor locked, quit—nothing—dispelling any myths of such characteristics. These two ponies showed us a tight horse race with the advantage going to the Summit Fan, which weighs in at 436 lbs. dry—more than 35 lbs. less than the Trail RMK. The Arctic Cat M5 has a strong advantage in both power and traction.
Notta Lotta New
The 2006 500 and Fans all come built from established chassis and suspensions. The old timer is the Trail RMK, built on the Edge chassis that touts five years of refined mountain performance. The Edge chassis is more conventional in design for rider positioning, lending to more of a low rider feel in comparison to the class competition.
The front suspension is the Escape CRC trailing arms with Nitrex shock absorbers working 7.6 inches of travel.
The rear suspension is the well proven Dual Purpose Rail with a Nitrex shock up front and a Nitrex Select in the back, combining for 13.8 inches of travel.
This season is the third year for the Rev chassis, with its aggressive rider forward positioning and the second year for the Summit Fan in that chassis. This year brings a few refinements to the Rev platform, including a newly design windshield, brake lever, and skis. More importantly, it has a 1.5-inch lower front end ride height for flatter cornering and improved handling. A new calibration ensures bump softening capacity of the Motion Control Gas shock absorbers at 9 inches of travel on the RAS front end.
Out back is the SC-136 suspension with both shock absorbers being the Motion Control Gassers providing 13 inches of travel.
A Great Rookie Year
The Arctic Cat M5’s rookie year was a good one and, as a result, the 2006 M5 comes virtually unchanged in the chassis and suspension departments. The WF-2 (commonly referred to as the M-Series) chassis is more of a middle of the road unit concerning rider forward positioning—not as aggressive as the Rev, but more so than the conventional positioning of the Trail RMK. This lends to an easier transition from sit to stand up riding, with its narrower, taller seat, which is much like the Summit Rev.
The M5 front suspension is the AWS VI double wishbone A-arms with Ryde FX shock absorbers along with adjustable preload springs delivering 9.2 inches of travel.
The back suspension is the Fastrack Long Travel Slide-rail, complete with adjustable torsion springs, Ryde FX shocks and the Torque Sensing Link rear arm, with a whopping 17 inches of travel, by far the most among the entry-level snowmobiles.
The SnoWest test crew’s ride and characteristic impressions of the 500 and Fans after testing them at Daniels Summit are that the Polaris name speaks for itself because the Trail RMK is more adapted to trail-type conditions even though is does well off trail. The Summit Fan is more of an “all around” package that has good performance traits both on trail and off, whereas the M5 is geared toward making tracks—and that would be fresh tracks off trail.
So needless to say, since we’re mountain guys who prefer to be off trail, we give the nod to the Cat chassis for being the most accommodating to boondock riding. The general consensus among SnowTesters was that the M5 also had a slight advantage in overall suspension performance. Our opinion is that all three would see big benefits from the installation of better shocks.
Now that we have scrutinized the main components of the 500 and Fans, let’s see who’s got what as far as standard features and available options. All three sleds have mountain specific skis, handlebars with a mountain bar or strap, running boards with some form of footing traction, rear cargo rack, adjustable hand grip and throttle lever heat and odometer/speedometer.
The M5 and Summit Fan have adjustable ski stance, the Summit Fan and Trail RMK come with electronic reverse and the Summit Fan and M5 have removable side panels. The Summit Fan also has adjustable toe holds whereas the M5 is finished out with hooked handlebar ends, tachometer and flat footboards with integrated heat exchangers. The M5 also has a main color option—that being either Arctic Cat green or black.
As we analyze the list of creature comforts, one would assume that the Cat would have a definite advantage again but our test staffers are all big (and I mean really big) proponents of the electronic reverse found on the Doo and Polaris. It would take a long list of goodies to equal the practicality and function of this one feature that we feel could end up being the single best innovation of the decade when it’s all said and done. So we have the reversers (Ski-Doo and Polaris) edging out the M5 in this category.
Even though we have these three sleds huddled together playing the same game, it’s rather apparent that the Arctic Cat M5 is in a league of its own.
An insurmountable advantage of 15 hp and a longer, more aggressive track is expounded when you punch your own line in the fresh snow on board the Cat. Our test staff agrees that the M5 is competitively priced in relation to the 550 fanners—just more than $500 over the Summit Fan and $700 more than the Trail RMK.
The Polaris Trail RMK and Ski-Doo Summit Fan are built to fulfill a very small niche for the consumer and it is completed with a bit of style and class. That niche is for an inexpensive machine that is moderately powered and thrifty to operate. Our testing in the Uinta Mountains reconfirmed the dissimilarity of the riding and handling traits between the two, yet general functions and performance comparisons showed the Trail RMK and Summit Fan to be very similar.
If you don’t bleed a particular color and/or don’t have a preference in chassis design/rider position, making a purchasing decision could have a strong reflection on dealer representation.
The Doo scored better than the Polaris by virtue of its lighter weight and more aggressive track.