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Well, it's not like it was hard choosing the "just right for me" high- performance 600 last year. You could have a REV and a similar Polaris IQ. The new F6 Arctic Cat was OK, and even the Vector-based Yamaha Nytro had some fans.
Decisions weren't complicated. The hardcore mogul buster would go for the Ski-Doo or Polaris. The diehard Cat guys would stick with Cat, and the guy who wanted a 4-stroke and pretend that it was equal to a REV or IQ would go for the Nytro. That was last year. It gets a bit more complicated this season.
That's because Yamaha comes with a serious mogul pounder in a new snocross-based chassis that brings the all-new Nytro's weight about equal to last season's REV and IQ. Add a new 4-stroke triple with 138 horsepower. The combination of power and reduced weight gives it a power-to-weight ratio that would meet or beat last year's competition. But it's not enough!
Why? Ski-Doo reinvented the REV, moving the target others were aiming for.
Putting the famed Rotax 600 twin into a much lighter, better handling chassis with vastly improved rider-friendly ergonomics makes the new REV-XP the easy top choice for the mogul-pounder of the year. Where it gets tough, is picking a No. 2. Right behind are the new Nytro, a revamped Polaris Dragon with a 600cc twin and Cat's comfy F6 Sno Pro.
Next year might not be any easier as we gotta figure there's a more ferocious Cat coming that may have the Doo-it-themself crowd envious. We suspect a new limited-build mogul machine that appeals directly to the Firecat faithful. Don't be too surprised to see Polaris expanding on its limited-build RR (race replica) model, which may strike a chord with loyal Polaris riders. Meanwhile, look for Ski-Doo to further update the XP and for Yamaha to continue working on trimming pounds.
For this season though, there are four super competitive 600cc high-performance models led by Ski-Doo's REV-XP MXZ Adrenaline. It's a virtual tie for second, depending on your leanings.
Ski-Doo REV-XP MXZ AdrenalineThe real super mogul sled from Ski-Doo is its limited-build MXZ X, offered as an early season model. It came with a few more features not standard on the MXZ Adrenaline. If you can find one, get the X edition, although you won't be disappointed by a standard Adrenaline.
One of our all-time favorite engines powers the REV-XP Adrenaline. Rotax's 600cc sequential digital injection equipped twin makes a solid 119 horses from power exhaust valves, a performance-tuned exhaust and precision injection from its throttle bodies. It has been one of Ski-Doo's most reliable motors for years. With smooth low end, a midrange that comes on easy and builds to a strong top end, the Rotax twin improves its power-to-weight ratio for '08 as Ski-Doo engineers cut roughly 50 lbs. from the chassis, steering and overall design of the REV-XP. Ski-Doo's claimed weight is 428 lbs.
When you park your '08 MXZ this winter, it'll be immediately obvious that this is something different. Even non-snowmobilers will notice the angular stealth fighter like shape. It's light, lean and ready for action!
You can really move in this redesigned saddle too. Seating is taller and the base is longer. It gives the rider much greater leeway to move and shift side-to-side for aggressive cornering or to push back for comfort on those long rails-to-trails groomed corridors.
The competition played up the limited seat mobility on the old REV compared to its own more rider-friendly seating designs. It was one of the few areas where the REV was vulnerable to criticism. All three competitors whacked the REV as they came in with their redesigned models that moved the rider forward. Now REV-XP whacks back and removes limited seating mobility as an objection.
This new XP also undercuts the competition's weights. But Ski-Doo's "one-piece-multiple-functions" design philosophy differs from Yamaha's proprietary casting process, where a single piece is cast with multiple functions designed into it. That's how Yamaha cut so much weight from the '08 Nytro.
One simple fact remains. This new XP chassis, especially the MXZ Adrenaline, gives you a light, responsive machine and stands alone in its handling uniqueness.
While the Cat and Polaris will seem familiar when you challenge a trail, the Adrenaline requires a bit of getting used to. That's because it's so light and responsive that you can do things with it that you haven't done with a trail sled in many seasons. YOU dictate the handling. The sled feels neutral.
You can change your mind - in the turn - where you want the sled to go through a combination of moving your body and throttling the SDI power. Previous REVs were more like the current Polaris Dragon, which wants you to commit as you turn in and not waver, unless you have totally mucked up the line.
Although the driveline sits higher than last year to allow a taller seating position, the XP is not top heavy, as the engine sits lower and the center of gravity remains low. Use your body to counter any roll. As with all current 600 mogul sleds, the MXZ's wide footboards allow you to stand in the rough, prepare for deep dips and quick rises.
The new Adrenaline is well suited for hard riding or high mileage. What's not to like?
2008 Ski-Doo MXZ 600 H.O. SDI AdrenalineEngine: 800R PowerTEK liquid twin 2-stroke
HP: 119.8*
Exhaust: Single tuned pipe
Ski Stance: 47 in.
Front Susp.: REV-XP
Rear Susp.: SC-5
Track: 15x120x1.0 in.
Fuel Tank: 10.6 gal.
Dry Weight: 428 lbs.
Price: $8,799 US/$11,449 CA
*Independent
AmSnow/Dynoport dyno test
Polaris Dragon 600Last year's Dragon didn't have any competition. At 700cc, the Polaris fit between the Ski-Doo REV 800 and 600. There wasn't a comparable Cat or Yamaha. Enter the Dragon 600.
It fits nicely into a very competitive slot. Were it not for the reinvented REV-XP, the Dragon would be getting a lot of hype. It's as good as the IQ chassis has gotten and is a suitable smaller displacement kin to last year's popular 700.
The Dragon 600 should be equally popular as it comes with the Polaris-built Liberty 600 twin that, at a claimed 125 horses, features a bit more punch than the Rotax 600. It's equally dependable and suitable for mogul-pounding. Cleanfire injection makes for quick throttle response as it calibrates the electrical pulses for temperature, barometric pressure and engine need.
Dragon derives a season's worth of suspension knowledge from the 700. Polaris engineers have turned the IQ A-arm front suspension around from its first appearance in the failed Fusion 900. The skis too have evolved to provide precise tracking in virtually all conditions. Front-end geometry is the most positive of any Polaris suspension and accounts for the rider's ability to charge into a corner and hold the line.
The IQ chassis and suspensions help this sled forgive rider indiscretions and stay stable. It's set up to handle rough trails with the ability to corner like a racer. Credit Polaris engineering with changing the Fusion-style front end and setting the IQ suspensions on a course that made them a success. Sure-footed with 10 inches of travel, the IQ front end uses Ryde's new Air 2.0 shocks.
The rear suspension features a high-pressure gas shock with internal floating piston to control damping and rebound at the front of the suspension. A remote reservoir RydeFX shock is used in the rear of Polaris' slide-rail setup. Both control the suspension's 13.9 inches of travel.
Rider ergonomics are better than on last year's Dragon 700. The seat is firm, but not brutal. You can slide around for cornering agility, or, sit back for a long ride. The handlebars are adjustable, and the view over the bars is exceptional. The styling gives you the impression that you're on a smaller sled. It provides the wind protection of a cruiser, but with a small windshield.
We like the placement of the Polaris high-low heater controls for bar handles and thumb warmer. The quick "no-look" controls suit performance riders.
This will be a first choice for many Polaris fans as it finally puts some distance from the ill-conceived Fusion. The Dragon 600 is an excellent snowmobile befitting Polaris' heritage. After the Fusion, it seemed as if Polaris didn't have a clue about its tradition of performance. It's not speed, but handling and trail prowess that separate contenders from pretenders and this is a contender!
2008 Polaris 600 Dragon IQEngine: 599cc Liberty 2-stroke
HP: 125.4*
Exhaust: SC VES single
Ski Stance: 42.5 in.
Front Susp.: IQ
Rear Susp.: IQ
Track: 15x121x1.25-in. RipSaw
Fuel Tank: 11.7 gal.
Dry Weight: 476 lbs.
Price: $9,499 US/$11,999 CA
*Independent
AmSnow/Dynoport dyno test
Arctic Cat F6 Sno ProMost folks love the plush Arctic Cat F6 Sno Pro. It's the cushiest sports sled, has an engine with instant-response injection and its A-arm front and slide-rail rear suspension set the standard that others have followed.
When Cat came back into the sled biz after its near-death experience in the 1980s, its first crop of all-new Arctic Cats featured A-arm front ends. It was different and not widely accepted, as Polaris featured the Indy trailing arm design, Ski-Doo had its own trailing arm version and Yamaha featured a strut design. Cat alone developed the Arctic Wishbone Suspension. Today, though, AWS is just one of four A-arm front suspensions, but Cat is arguably the best for comfort and versatility.
The F6 Sno Pro features a taut front end with the seventh generation AWS offering 9.5 inches of travel. AWS VII relies on Fox Float shocks and a specially calibrated sway bar to minimize roll when cornering. Gripping the snow, are plastic saddleless skis with dual runners.
Maintaining control at the Sno Pro's rear, is a Slide-Action suspension with torsion springs and Fox shocks with internal floating pistons. Cat engineering has the slide-rail suspension design down cold. After all, it was Cat engineering that developed the first production slide-rail design in the late 1960s. Today's version offers up to 13.5 inches of travel from the coupled design. Coupling blocks help smooth the transition of bumps from front to rear as well as help keep skis from popping off the snow under quick acceleration.
The 599cc Suzuki-built twin won't pop the front end like the 1.0-liter Cat motor, but it will give you solid performance on the trail and in the bumps. It comes with Arctic's power valve technology to provide smooth low-end performance while maximizing top-end running. The exhaust is typical for this segment with both cylinders' exhaust channeled into a single canister.
Cat engineers were some of the first to play with batteryless injection, which means that the F6 should get under power by the second pull of the recoil cord. Electric start is optional.
The F6 delivers smooth Suzuki power to the track via Cat's unique planetary gear system, which takes out the driveline's rough engagement.
The Cat features what Arctic marketers call Twin Spar chassis design. It's similar to what Ski-Doo and Yamaha have done to relocate the engine while creating a more enhanced rider area. This design allows the engine to sit low while raising the seat for better ergos.
In Cat's case, the cockpit is uniquely adjustable to also help ergos. The seat has seven settings and suits a vast array of body types. Add in the adjustability of the handlebars and footrests, and you have a sports sled that can fit just about any riding style. While the adjustable bar is a clever idea, the Cat engineers were smart enough to keep the hooked bar ends, the best in the business. Unlike some other designs, the curved bar is designed in, not bolted on as an accessory. It's a feature that makes the Sno Pro so controllable on the trail.
Yet, with all of its performance heritage, the F6 Sno Pro feels too "civilized" compared to the REV or Dragon, both of which have more edgy personalities. This Cat is too nice. It's very comfortable, but that makes it a bit bloated for some riders. Despite the extensive use of lightweight aluminum in the Twin Spar's components, the F6 feels heavier than the Polaris and new Ski-Doo. We feel that the Cat trails in performance criteria to others in this group. But, if you like your sports sleds with conveniences and an ability to be custom- fitted to your riding style, the F6 is perfect. It's a good performer with best-in-the-business ergonomics.
That's all before you start checking out the information-packed deluxe instrument center with digital/analog speedometer and odometer. This Cat has it all - except the wild streak serious mogul pounders demand. That seems odd to us, a Cat that's too civilized for the hardcore rider? Can it be?
2008 Arctic Cat F6 Sno ProEngine: 599cc 2-stroke
HP: 118.2*
Exhaust: APV w/tuned pipe, pipe sensor & canister
Ski Stance: 43 in.
Front Susp.: AWS VII double-wishbone A-arms
Rear Susp.: Slide-action frame w/coupling blocks
Track: 15x128x1.25-in. Cobra
Fuel Tank: 10.6 gal.
Dry Weight: NA (495 lbs., 2007 model)
Price: $9,499 US/$11,999 CA
*Independent
AmSnow/Dynoport dyno test
Yamaha Nytro RTXImagine you're a Yamaha engineer committed to 4-stroke engines in sleds creating high-performance 4-stroke sleds, but you're criticized because they're heavier than comparable 2-strokes. No one says what a great job you've done in creating a rider-friendly sled that uses less fuel, less oil, is extremely dependable and will require less service than the 2-strokers.
Now, imagine that you work even harder, find ways to engineer your 4-stroke design down to within pounds of the best selling 2-stroke performance sled and you have a lighter 4-stroke with a power-to-weight ratio equal to, or better than, anything else in the 600 rough-trail category. You've created a great sled, all-new engine, chassis, ergonomics and you're ready to put a serious move on the competition. Except, the competition didn't stand still. It created a better, lighter sled.
Meet the Yamaha Nytro RTX, Yamaha's best ever 4-stroke sports sled with an all-new 3-cylinder engine that pumps out a ferocious 138.6 horsepower, giving it a power-to-weight ratio similar to the 150-horse Yamaha Apex. It's a carefully crafted, brilliantly engineered machine. But nearly 100 lbs. heavier than the lesser powered Ski-Doo MXZ Adrenaline 600 SDI!
Let's forget the weight. What makes the Nytro RTX a great sled?
First, Yamaha created a new 1050cc fuel-injected triple. The Genesis 130FI has excellent midrange. When we first tested the RTX, Yamaha had yet to add the coupling setup to the rear suspension. Open the injectors, and you needed to hold on as the skis popped savagely off the snow. OK in a straight line, but the raised skis were bad news powering out of turns. Thankfully, by our March test session, the coupling setup was in place and the RTX was tamed down. The engine hit hard, but the weight transfer was under control and the skis stayed on the snow!
The Nytro has power! No other sledmaker has managed to create such 4-stroke engines with the response of a 2-stroke, but with 4-stroke advantages of improved fuel efficiency, cleaner emissions, minimal oil use and high reliability.
Also, the 130FI is the first Yamaha 4-stroke to use engine-braking reduction, a feature of Arctic Cat's 4-stroke motor. Previously, Yamaha had frowned on the concept. The system makes the 4-stroke freewheel like a 2-stroke, making the Nytro RTX coast like an ordinary 2-stroke sled when you let off the throttle.
Where Yamaha scores big is in the chassis design. It outdoes the original REV in rider ergonomics. You get a very aggressive - yet comfortable - riding position. You can easily move from side-to-side or back-to-front. The floorboards are wide and positioned for standup riding in the big bumps. The handlebars are upright for standup, but angled to be comfortable on groomed trail sections. The bars are a close match to Cat's curved and hooked bars. Nytro's setup is excellent.
With the chassis designed to locate the engine low and centered, the rider sits atop a very maneuverable mount. Fortunately, while the new saddle is narrow, it is sculpted to provide better comfort than the narrow butt floss seating of Phazer models.
The front suspension is supple, but stiff enough to control offset bumps with ease. Yamaha uses Fox Float air-spring shocks up front, which are light and eliminate the need for the weight of coil-over-shock springs.
At the rear is a dual shock Yamaha design fitted with a pair of 40mm clicker shocks with remote reservoirs for shock cooling. The shocks can be calibrated to your personal taste for rebound and compression.
Nytro RTX handles well. It is especially adept in the big bumps, but it should be. It was specifically designed to be a rough-trail sled.
Yamaha's snocross team provided some input into the sled's design, and a very slightly modified Nytro won a snocross event last season. So, if it seems as though the Nytro has some racing blood and some physical attributes to last year's 4-stroke snocrosser, it's deliberate.
What wasn't deliberate was being a bit behind the redesigned REV-XP. But, Yamaha is not alone, all the sled manufacturers now have to play catch up.
The target has moved!
Who'll close the gap the quickest?
2008 Yamaha Nytro RTXEngine: 1049cc 4-stroke
HP: 138.6*
Exhaust: Rear single pipe
Ski Stance: 41.3 in.
Front Susp.: Independent double- wishbone
Rear Susp.: Dual Shock Pro
Track: 15x121x1.25-in. RipSaw
Fuel Tank: 7.4 gal.
Dry Weight: 520 lbs. (513 lbs., no reverse)
Price: $10,699 US ($10,399, no reverse)
*Independent
AmSnow/Dynoport dyno test