David Vs. Goliath

It's not really a very fair comparison between a quarterback and a linebacker. Each has a different role and set of skills on the field.

That's why we think it's the same kind of deal when it comes to, in general terms, comparing classes of mountain sleds. Snowmobiles designed for the West are made for different riding conditions and terrain, unlike trail sleds. With a trail sled, regardless of whether it's a 600, 800 or even a 1000, you can go the same places on a trail. With the bigger ccs, you just get to go faster.

Not so in the mountains. An 800 will usually outclimb a 600. An 800 will usually handle deeper snow better than a 600. Boondocking could be similar for both sizes of machine, depending on conditions-the 800 has the advantage in steeper terrain and deeper snow in the trees. What rocks in the flats doesn't necessarily shine in the mountains.

There are clear advantages to bigger snowmobiles in the West, although, interestingly enough includes the weight of the machines.

Why A 600

So why on earth would anyone want a mountain 600?

Because not everyone wants to highmark on the tallest mountain. Not everyone wants to frolic in the deepest of powder. Some riders want to dabble in hillclimbing, boondocking and deep powder riding but they don't feel the need for bragging rights. Others are new to the sport and really have no business on an 800 mountain sled-yet. Still others have a smaller frame and don't want to wrestle around a bigger (though, not always heavier) snowmobile.  

Not to mention, 600s are anywhere from $900 to$1,850 cheaper than an 800.

It's for those sledders that the 600 is an ideal snowmobile.

The SnoWest SnowTest staff has just about as much fun bangin' the hills and powering through the snow on the 600s as we do on the 800s or any other class.

It's all about a level playing field. If your group is made up of a mix of sleds-6s, 7s and 8s-well then, if you're riding a 600, you might not be able to keep up in certain conditions. However, if there are just 600s in your group, you can have a blast.

There are occasions when the 600 outdoes the 800. We've seen Jack Struthers, who can be classified as a small rider, take a 600 places where an 800 won't go. In those kinds of situations, it's the rider taking full advantage of the 600's power and agility to best the bigger sleds.

This year's lineup of 600s is very similar to the 2007 crop, minus one, the Yamaha RS Vector Mountain.

2008 Lineup

Back for another round is the Arctic Cat M6 (one model), Polaris 600 RMK (two models) and Ski-Doo Summit Adrenaline 600 (one model). There is a newcomer of sorts in this class, the Polaris RMK Shift, which is a base model of the 600.

Throw out the price differences between the 600s and bigger sleds and the obvious horsepower advantage of the 800s or 1000 and the 600s almost mirror their larger counterparts, except for Ski-Doo. Ski-Doo has moved its 800s into the much-hyped Rev-XP chassis while the 600 stays in the still functional Rev chassis.

Perhaps more than any other class in the mountains, the 600s are pretty equal-in power, ride and fun.

Since it seems all the talk in the mountain segment is about weight and horsepower, let's start there.

First disclaimer. We don't even really want to get into the weight issue. A couple of the manufacturers claim their 600s have lost weight from their 2007 to 2008 models but their own official dry weight figures don't support that. So, rather than get in a tussle about all that, we're reserving judgment until the SnoWest dealer shootout this winter when we weigh the machines ourselves. Seat of the pants riding tells us all three 600s are within a few pounds of each other and handle that way, too-unlike in 2007 when the Yamaha RS Vector Mountain was at an obvious disadvantage compared to the other three.

Second disclaimer. Snow conditions during last spring's photo shoots were less than ideal for testing just about everything-horsepower, ride, powder riding, you name it. But we did our best to find some untracked snow, climb and boondock through the trees. Here's how the official horsepower readings shake out.

Arctic Cat M6                118-120

Polaris 600 RMK 144     118

Polaris 600 RMK Shift    118

Polaris 600 RMK 155     125

Ski-Doo Summit 600                  120

Power Hungry

The SnowTest staff agreed the Polaris 6 edged the Ski-Doo 6 in power, but not by much, and only in certain conditions. If we were to do it all over again, the results might be different. Some praised the "very snappy" bottom end on the 6 RMK while another said, the throttle response on the Summit 6 was "quick-best in its class." Still another said the M6 had a "very smooth powerband."

One telling point in the horsepower arena came when we came to Chicken Hill, a spot near Grand Lake, CO, famous for hillclimbing. It's a wide open mountain face that gets steeper as you near the top.

We couldn't resist competing in an uphill drag race on Chicken Hill. The snow was set up, and for the most part, pounded out with use, so the riding surface was fast. Visual results from several "challenges" showed the Summit 600 first off the line with the M6 second and 600 RMK third. That was from a dead stop and then hammering the throttle. When we started the drags on a rolling start, it was pretty even between the three machines.

The Cat is powered by a Suzuki 599cc liquid-cooled twin with batteryless EFI. The Polaris 600 with 144-inch track and 600 RMK Shift both have a carbed 599cc Liberty twin while the 600 RMK with a 155-inch track features a high output Cleanfire injection Liberty twin (that accounts for the 7 hp difference). The Summit 6 has a Rotax 599cc twin with electronic semi-direct injection.

While it may not appear that the staff on the SnowTest crew disagrees on the sleds we ride, it does happen. Case in point is the 600 RMK. One SnowTester said about the carbed version, "all aspects of the motor are very good and a touch better than the CFI." Another said, "I thought the CFI was crisper than the carbed model."

Going with that thought, we expect the Cleanfire injected 600 RMK to be more crisp in throttle response than the carb version, but then, for those who like to tinker and tune, there are fewer opportunities to do so on the fuel-injected model compared to what you can do to the carb model.

If you've decided to go with a 600 chances are horsepower isn't a high priority (unless you're using reverse psychology-smaller is better). How a sled rides and handles is another story.

In The Bumps

When it came to how the sleds handled the bumps on and off trail, the nod went to the RMKs, followed by the M6, which features a new rear suspension for '08. The primary complaint on the Ski-Doo was "a darty, aggressive front end" which skews the sled's handling in the big bumps. Another SnowTester said about the Summit 600, "It just doesn't do as well in the bumps as the other 600s. It seems to bottom out more." Commenting on the 600 RMK (both the 144 and 155) ride, "Suspension performance was very good overall-best in its class. Good to very good on and off trail, especially considering the tall seat."

Each SnowTester commented about Cat's new and improved rear suspension, which features a much appreciated Fox Float shock-among other changes-in the rear skid, helping to soak up the big bumps. "It's a better ride in the deep moguls," one Snowtester said. "A little bouncy but not like it used to be." Another said, "Still a little happy but it has come a long way. The sled's narrow chassis is surprisingly stable in the whoops."

Another appreciated improvement in the Cat's handling is the new spindles, which utilize Cat's Sno Pro design for a 10-degree tighter turning radius.

Loosely connected to a sled's handling is the seat. The trend has been for sled makers to go with a narrow, taller seat for western riders who stand a lot while riding, climbing and boondocking. Taller seats make it much easier to transition from sitting to standing and more narrow means not having to throw your leg over as much territory. Both Polaris and Arctic Cat got good marks for their seats with the biggest knock against Ski-Doo being the seat was too low, increasing the effort it takes to go from sitting to standing. Cat has gone with a new material on its seat, making it more "grippy" but not too much. There was some talk about Polaris' seat being too narrow to kneel on when stand up riding, but the talk is spotty.

It seems the SnowTest crew has been on a running board kick lately. This was an especially hot topic a winter ago when every ride was a powder ride and buildup on the running boards was a big deal. Last winter? Not so much. That didn't stop Cat from coming out with probably the best new design on snow which results very little snow buildup (and we really tried to find some snow to test that very thing.) Ski-Doo's running boards are decent but we're waiting for the day when the Summit 6 gets the same setup as the Rev-XP. Those running boards are also some of the best out there. We're guessing that the Summit 6 will move to the highly touted Rev-XP chassis next year.

Not to beat a dead horse, but with the snow conditions the way they were, floatation didn't really come into play much at all. When it did, Ski-Doo's 16-inch wide track got the best reviews, even though its 144 inches long compared to Polaris' 155 and Cat's 153. Polaris has the shortest lugs (and longest) in the class at two inches on its 144-inch track while Cat and Ski-Doo both have 2.25-inch deep lugs. On Polaris' 155-inch track, the lugs are 2.4 inches.

Just a word about the RMK Shift, which looks pretty much plain Jane on the outside. Despite its appearance, this Polaris 6 has all the same features as the other 600 RMKs-it just comes in black. Polaris purposefully left this sled "naked" so buyers could customize it with their own graphics ideas or just leave it the way it is. Of course Polaris offers several different graphics packages (like Pink Diva or Flaming Skulls) to choose from. At $8,399 the Shift costs more than the 600 RMK with a 144 ($7,999) but less than the 600 RMK 155 ($8,749). The SnowTest crew doesn't have any feelings either way, we see it just as another option.

And with the offerings in the 600 class, any option you go with is a good one. There are no bad apples in this class.

That's what makes the playing field so level-even though we prefer to be going up or down in the mountains on these 600s.