The March 2008 issue of SnowTech mails to subscribers on March 13th. Mail time to US subscribers could be anywhere from a few days to 2 weeks. Canadian subscriptions should show up in 1-3 weeks.

The March issue is 108 pages. Contains a special 32 page section on the newly released 2009 models from all 4 manufacturers. Long Term test reports on 10 different sleds from SnowTech’s 2008-09 test sled fleet - including a 2,000 mile test on Ski-Doo’s new 600 HO E-TEC.

This issue will begin showing up on the newsstand about the 20th of March. The next issue of SnowTech will be the September 2008 issue and will mail the first week of August.

The all-new 2008 Yamaha FX Nytros are true big-bump, rough trail rider-forward four-strokes. Fitted with a stiff chassis and capable suspensions, the FX Nytro truly brings four-stroke performance to an all-new level. And, they keep getting lighter.

With the introduction of the Yamaha Phazer last year, it became clear that Yamaha could indeed make a viable rider-forward four-stroke sled that was as light as a comparable two-stroke (electric start and reverse). The ergonomics were there, with the rider in the right place to manhandle the sled and better isolated from the bumps. And, the balance was far better for transition riding; where you transition from being seated to standing as conditions required.
Problem was, the Phazer was underpowered for most experienced snowmobilers, despite its high fun factor. 80 HP becomes very rider-weight sensitive, so one immediately had to wonder what would happen if we were to drop a larger engine (or at least one with more power) into its rigid chassis

Logically, since Yamaha had mated a pair of their 250cc four-stroke dirt bike engines to make the 500cc Phazer, why couldn’t they do the same with a couple of 450cc dirt bike engines as well? That’d be one mean 900cc Phazer. Why not?

Yamaha told us they’d already looked at that, and that after the required crank balancing and reinforcement, it would be so close (within a couple of pounds) to the existing three-cylinder Vector engine that it wouldn’t be cost effective to do so.

Bummer. At least it made sense.

Then, when the snocross race season started, we all saw the FX Nytro as a race prototype and the writing was on the wall. It looked very much like a Phazer in construction and design, but it was bigger. Yamaha doesn’t just take an existing chassis and drop in a bigger motor, that wouldn’t be optimum. They took the basic layout and design features of the Phazer, but pretty much ended up with another unique chassis and platform from which to build the FX Nytro family upon.

The engine was bumped up to 1050cc, the max allowed under current snocross rules. EFI was added, along with a host of other detail items to make the Genesis 130 really rip. The engine is likely the strongest part of this sled. The performance is sure to exceed most expectations and should do so reliably and consistently, without being as heavy as the Apex models (an Apex GT dry spec is 560 pounds). In contrast, the dry weight spec of the FX Nytro is now down to 513 (no reverse) and 520-522 with reverse.

The engine lights up with such fast throttle response you can’t help but be impressed with the engine and the torque and the way it pulls your arms, hard. The 130 HP figure doesn’t do justice to the torque this things makes (at least the protos all pulled like a freight train). Remember, the engine got bumped up to 1050cc, and it is faster-revving due to a lighter crankshaft (1.7 pounds lighter than the Genesis 120’s).

It also acts way different than the previous Yamaha four-strokes in that it coasts down easier with an Engine Braking Reduction system - so there’s far less compression braking when you get out of the throttle. We really like this, as it makes the sled way more two-stroke like in its mannerisms.

How’d they do this? It’s in the fuel injection system, surprisingly. A small bypass circuit opens and closes, based on data inputs, to allow some air to pass through and reduce the pressure in the cylinders that cause engine compression braking. It is not adjustable, yet it works amazingly well.

What really jumps out is the throttle response. The calibration of this engine and its running quality has been most impressive in our prototype testing, spot on and crisp and clean, as has been the clutching and gearing set-up. We have no issues here at all. It has 11:1 compression ratio, but is designed to run best on 87 Octane pump gas. The engine itself weighs 10.2 pounds less than the Genesis 120 engine. It delivers all the 4-stroke benefits-fuel efficient, wide power band, reliable, no smoke, no injector oil.

Now realize, the race sled version was used to validate many of the design elements found on the consumer versions, which retain much of the character of a true race sled. There isn’t much in the form of rider protection, much like the “naked” Phazer or Ski-Doo REV models, or any of the race sleds, for that matter, but this nakedness allows you to see what’s out in front of you, and you can really see the ski tips.

Like a race sled, the fuel tank is small; capacity is only 7.4 gallons, and that’s barely a 100 mile range at 15 mpg. And there’s minimal cargo or storage capability out of the box. So logically, this is not the ideal sled for all-day long trail rides. The new RS Vector models that combine the (carbed) Genesis 120 engine into the rider-forward Apex chassis with a re-calibrated Mono Shock RA rear suspension are far better suited for this task.

What the FX Nytro is going to excel at is these two models are the best rough trail sleds Yamaha offers. They don’t go as far as to call them cross country sleds, but they truly do compare to the Polaris Dragon models, the Ski-Doo MX Zs (X-packages and Adrenalines) and the Arctic Cat F-Series, standards and Sno Pros. Yamaha hasn’t really had a sled with this kind of capability for, well, when was the last time? Maybe back to the SX-R? The SX Viper really wasn’t a rough trail sled; that was more of a slot car than a bump sled, despite the suspension calibration.

So when you hop on the FX Nytro, the sensation is one of a bigger Phazer, more so that a trimmed down Vector. Going down the trail it is lighter than a Vector or Apex, but noticeably heavier up front than a Phazer. The FX chassis with sport rider-forward position puts the rider in an aggressive, yet comfortable, forward posture, with the engine down low and back in the chassis. This gives the FX Nytro a very centralized mass. Its CF die cast and tube chassis members make the sled very stiff and very light. The rigidness of the design creates a stable platform for the suspensions to do their work.

Yamaha worked like crazy through the winter getting the suspension calibrations dialed, and each time we rode the FX Nytro models they were getting better and better. The rear suspensions on both models have been quite firm every time we’ve been on them. Not what we’d want to call trail-compliant, but in all fairness we will reserve judgment until we see how the final production calibration performs this fall. For reference, we expect the standard FX Nytro to be very comparable to a (2007) Ski-Doo MX Z Blizzard (or Adrenaline), with the RTX more X-package like.

The handling of the FX Nytro is really quite good, more like a Ski-Doo MX Z than it is a Polaris IQ or Cat F-Series. The IQs and F-Series are all going to have lighter, easier steering, but the Nytro will likely be more precise, like a Ski-Doo would be, generally.

So, if you’re into true rough-trail performance, or the type of riding that consists of ungroomed forest roads, then this is going to be the better suspension calibration match out of the Yamaha line-up. Sit-down trail riders will find greater comfort and compliance in the Apex and Vector models, but those sleds will not be as capable through the rough at higher speeds, nor will they have quite the precise steering or nimble agility afforded by the lighter weight and suspension selection. We can’t go as far as calling it a cross-country sled, as that really would require a 136” or 144” version (2009?) to tackle the deeper snow that category would also consist of.

The 2008 Yamaha FX Nytro retails for $9,999, offered in Team Yamaha blue and white, or a classy white and yellow package. The firmer “Rough Trail” FX Nytro RTX is as close as you can get to the Yamaha Pro Open Race sled. It sells for $10,399 ($10,699 with reverse) and the 40th Anniversary white & red version goes for $10,899.

Ski-Doo really had a big task facing them. With the REV taking the industry by storm back in 2003, it had risen to the top of the world and it was five years into its cycle. The other sled makers were catching up, and passing it in some regards, so it was time to once again move the target. But, how do you improve upon it? How do you once again make it bigger, better, and worthy of your consideration?

It’s not like Ski-Doo riders were complaining about the weight of the REV models. About the most valid complaint was that since Ski-Doo had introduced the “rider-forward” ergonomics, the rest of the industry had analyzed the rider positioning and tweaked it so the knee angle wasn’t as tight as the REV. Many of us felt the Arctic Cat F-Series and Yamaha Phazer models had improved upon the REV seating position with a more relaxed knee angle. The key was to keep the hips above the knees so standing was easy, so it could be done using your legs instead of having to bench press your entire body weight with your arms when you wanted to stand.

Ski-Doo had also been watching Yamaha, very closely. They saw how the four-strokes were gaining popularity, and how with each passing year they were getting lighter and lighter. Then, the Phazer and Apex models truly featured rider-forward ergonomics. The four-stroke engines were mighty and very reliable, but they really didn’t have anything over the SDIs in fuel economy.

However, the XP didn’t come about as a reaction. Its development started as soon as the REV itself was validated, so Ski-Doo next set their sights on doing it “right”. The REV was really a stop-gap sled in the sense it was built from a new, solid chassis, but the rest of the platform was using existing components. To go all-new at that time would have been too risky. So, with rider-forward proven, they set out to make an all-new sled with rider-forward ergonomics, but to do it with this in mind from the get-go.

Basically, every part and piece had to reapply for its job. Logically, their engines were a huge investment so they kept them intact, as the next wave of EPA rules wasn’t until 2010, they could use their existing engines for a couple more years. But the rest of the sled was analyzed and redesigned as if they were a start-up company that didn’t have parts bins full of pieces to utilize. This meant new tooling, new parts, new everything. Very expensive and very risky. But, the result would (hopefully) be so impressive it would force the other sled makers to reel.

The Yamahas were getting really close in weight to the REVs, so Ski-Doo knew they could make their two-strokes so much lighter that there would again be a significant weight difference. Ski-Doo asked us how much weight would be a “significant” difference, and we all told them 25 pounds would be huge. So, they aimed for 50. Go figure!
OK, here we go. The new REV XP (eXtra Performance) models are about fifty pounds lighter, across the board. About the only parts left over are the engines, primary clutch, skis, coupler blocks, and maybe the left handlebar control block. Maybe a few bolts here and there, but everything else is all-new.

Not only did they computer-analyze each and every part and make it as light and multi-tasking as possible, they also wanted to re-arrange the components to get our feet where they wanted them. They knew rider-forward was valid, but they also wanted to let us open up that knee angle and get some comfort back that had been lost in moving the rider forward on the REV. With the REV, the secondary clutch and jackshaft was the limiting factor, so this was relocated up and forward so we can now place our feet in this valuable location (right alongside the drive axle). The result is the ability to ride aggressively AND more relaxed, as you can move your feet EIGHT inches further forward than before. No longer are they locked in place.
During the development of the REV XP models, Ski-Doo realized something profound. Their MX Z Trail, the 500SS value sled, was within striking distance of the magical 400 pound mark. They could, with some tricks and lighter parts, make a 500 SS model that broke the 400 pound (dry spec) mark.

Enter the MX Z TNT. It has a dry weight spec of 399 pounds (the prototypes were 392, but they gave themselves a couple of pounds to work with as production seems to add a couple here and there). They started with their rock-solid 500SS engine package (actually the 600 liquid engine that originated with the first ZX Summit 600) and did what they had to make it a jazzed-up version of their MX Z Trail (gas cell suspension 500SS value sled).

The MX Z TNT blows away the competition when it comes to weight. It is said to be 82-88 pounds lighter than the Polaris 500 XC SP, Arctic Cat F5 EFI and Yamaha Phazer. Over eighty pounds lighter. That’s a lot of cheeseburgers.

To offer a 600 liquid-cooled sled at under 400 pounds takes some time to comprehend. The last time we recall such a comparable feat was with the original fan-cooled Phazer that came in at under 400 pounds, but that was like twenty+ (24) years ago.

A sled this light translates to a level of responsiveness only hinted at by snowmobiles of the past. It is almost a telepathic bond between you and the sled that allows for responsive handling that has to be experienced to be understood. You move, it responds. Terms like agility, flickability, responsiveness, lightweight, they all pale in comparison to the reality. It’s like a toy underneath you. You don’t drive it, you ride it. You don’t steer it, you manhandle it. And with your feet forward (but you centered) you can again leverage the chassis with your feet. Maybe they should have called it REV-PLUS.

OK, so we like the TNT. What don’t we like about it? It is a fairly cold sled to ride, as were the REVs. Wind protection is marginal with the minimalist front end. The packaging is very tight, as the mechanics were placed and then the stylists formed the panels around the sled. The stealthy design looks futuristic and fast, even standing still. The diamond-pattern is called “faceted” design.

Our prototype testing of the TNT indicates it is way lighter than anything else in recent memory. The handling is precise, with surprisingly light steering effort for a Ski-Doo. It isn’t what we’d call squirrelly, but it isn’t a sit-back-and-relax cruiser by any means. It requires less constant attention than the first REV models, so most anyone should be able to acclimate to the sled. Hanging on for a long day’s ride doesn’t require as much effort since you don’t have to horse around the extra 80-100 pounds.

Where we noticed the most need for improvement was in the rear suspension. This was true with all of the XP models, in that the new SC-5 suspension wasn’t up to the performance level in prototype form that it should be, so we’re going to have to wait and see what the production sleds work like. With this much of a radical change, it will take some time to get the suspensions tweaked and fine-tuned. It wasn’t until the fourth year of production that the REV suspensions really came into their own, so we’d expect the XP suspensions to get better with each year as well.

With under 400 pounds to haul around, the proven 500SS engine package works very well. This engine still makes about 108 HP, and despite being carbed, our testing has shown it is very close to the 600 SDI in real-world fuel economy, so don’t think the SDI is going to be head and shoulders better than the SS. They’re pretty close out on the trail.

How does the TNT differ from the MX Z Trail (500SS)? The Trail has gas cell shocks, the TNT has HPG Take Aparts all around. The TNT gets taller handlebars with hooks, and a host of lightweight parts from the X-packages that also help shave 16 pounds off, in comparison to the Trail. The biggest difference, performance-wise, will be the suspension calibration, with the TNT more capable through the rough, with the Trail more of a groomed trail sled than a bump sled. The TNT could have been called a 500X, but then it wouldn’t stand out.

Bottom line; the Ski-Doo MX Z TNT is an explosive little rocket that brings back the fun factor of smaller and lighter sleds that don’t break the bank. Whether it is still durable remains to be seen, but we have no reason to believe it won’t be everything that you’d expect. Whether blasting down a forest road, groomed trail, across the lake, or through the meadows, the TNT is going to be one of the hottest sleds of 2008, and yes; it truly has the potential to be bigger than the original REV.
The 2008 Ski-Doo MX Z TNT sells for $7,649.

The Arctic Cat F-Series machines demonstrate what happens when a sled is given a strong chassis for the suspensions to work under, and how the handling and ride character of a snowmobile can be influenced by placing the rider in a centered position. The Twin Spar chassis found on all F-Series models demonstrated this in 2007, and for 2008 there are really only detail changes that improve upon the 2007’s stellar performance as trail sleds.

There are a large number of Arctic Cat riders who haven’t even tried an F-Series sled, and they really don’t know what they’re missing. Instead of going for a smaller, sleeker appearance like what the Ski-Doos and Yamahas have been chasing, Cat stuck to their guns and reminds us that snowmobiles are ridden in extreme conditions where rider protection remains an important benefit. Where many of the competitive sleds may “look” sleek, that appearance costs you protection from the elements, and are thus very cold to ride at temps much below zero.

Last year, both the standard and Sno Pro models came with the same track (1.0”) and dual-runners on the skis. This didn’t seem right, and Arctic Cat realized this so they’re going back to a 1.25” track on the Sno Pro models. It’s a new pattern from Camoplast called the “Cobra”, which is said to improve loose snow performance off-trail and provide a less positive tail lock than the Ripsaw (the Cobra will be a tad looser on the hardpack). The lightweight Cobra’s new design features rigid fingers connected by cupped sections that scoop the looser surface snow. The aggressive 1.25-inch lug features an additional 0.102-inch cutting edge and “stepped” fingers for improved traction in hard pack snow conditions, bringing the total lug height to 1.352 inches.
We’re not sure if the Sno Pros will also be fitted with a single carbide runner to go with the new track. If they don’t, they should. We’ll be putting them on immediately if they’re not that way out of the box.

In an effort to make the sleds handle more aggressively, the calibration of the front arm has been changed through a progressive front arm coil spring. This adds more ski pressure for more positive handling and less pushing, while retaining a light steering effort. This subtle change is very welcome. It also seems to deliver a plusher ride in the stutter bumps, yet retains composure and control in harsher terrain, something these sleds excel at, despite their added weight.

The Slide Action Rear Suspension is really a work of art for Arctic Cat, as the F-Series sleds will surprise and amaze most trail riders with the ride quality and bump isolation they provide. We would have to declare the 2007 F-Series sleds we logged thousands of miles on as being the best riding sleds of the year when it came to ride comfort. Our test riders would fight over who would get to ride our F6 Sno Pro and F8 when the trails or forest roads were going to be rough that day. We fully expect Arctic Cat to once again have the best riding trail sleds for 2008, as well.

A new sway bar is smaller and lighter, with its mounting points on the a-arms further outboard, coupled to new composite blocks to reduce sticktion. Coming hard into a corner you don’t have an initial amount of body roll then have the sway bar kick in. Now, the sway bar effect is more consistent as there is little, if any, binding in comparison to the 2007s (that could exhibit a slight roll, then when the block would let go of the sway bar, it’d flatten out).

Another handling improvement can be found in the rear suspension, as the limiter strap gets some holes put back in for those who like to vary the strap length for specific handling requirements. While most trail riders will simply add carbide or more aggressive skis to get the handling response they’re after, the ability to vary the limiter strap length is still used by some riders for their unique conditions or preferences.
And in what we consider to be the most noticeable difference is the addition of a truly functional mid-height windshield to the standard models. Last year both the standards and Sno Pros came with a lacking (but go-fast) windshield.

Arctic Cat has recently informed us of additional changes that are being made to the 2008s in comparison to last year’s models. One problem area was with the honeycomb cover on the intake vents. Powder snow would pack into these, making it a bugger to wipe the snow out of them for a clean intake path. For 2008, the high-mounted intakes will resemble those found on the Crossfire and M-Series sleds, a wise change.

For a cosmetic improvement, the lower side panels and the lower portion of the rear tunnel plastic will now be textured instead of the smoother finish of 2007. This should reduce the visible scratching and buffing of the panels in these vulnerable areas.

As is typical from model year to model year, the EFI programming of the F6, F8 and F1000 models has been upgraded with revised fuel mapping that should increase the performance at any elevation. No mention has been made, however, of improvements in fuel economy. The throttle body EFIs run quite well, but they do use slightly more fuel than the four-strokes or the SDI/CFI injection systems used by Ski-Doo and Polaris.

From what we can tell, the F1000s will also be getting some tweaks to the clutching in the form of heavier flyweights, as the four-tower primary has been replaced with a more traditional three-tower primary. That means we’re now back to three flyweights instead of the four used in the 2007s. The F1000s are also coming with a multi-angle 46/40 helix in the secondary, which should quicken the upshift and enhance the acceleration of the big twin. F8s get new gearing as well, now 64/56 for improved top end performance, compared to 62/58 as used in the 2007s.

You’ll also find a new exhaust deflector on all Twin Spar chassis sleds, designed to better direct the spent gasses away from the side panel for less heat damage and soiling.

One minor gripe with the 2007s was the difficulty in getting the clutch guard off. Now this should be easier, as there’s a new 2-pin quick-pull design.

One other issue was with the way we would knock the rear-facing side panel vents out of the side panels with our knees. Quite often we’d find them laying down inside of the side panels, chewed up by the rotating secondary clutch or brake disc. This time around they have an improved locking design with longer tabs so we shouldn’t have to glue them in place any more.
And in the durability department, really aggressive riders were finding they were damaging the rear arm on the 2007s in extreme conditions. Cat’s cross country racers figured this one out, so they came up with a stronger rear arm that proved to work well in the race circuit.

Just like last year, there is a noticeable difference between the standard versions and the Sno Pro models. The faster you ride and the rougher it is, the better the Sno Pros will work in comparison to the standard ones. The standard sleds are excellent at typical trail conditions, and it really takes some hammering on them to need a Sno Pro, but there is a point at which the Sno Pro is going to be the better sled. And likewise, there is a point where the standard sleds are going to be more compliant through the stutter bumps, yet will bottom easier than a Sno Pro. There is no right or wrong here, it is really a matter of matching the calibration to your conditions and riding style. Younger riders typically go Sno Pro, a better fit for standing and rougher riding. Sit down riders and those not standing as much will find the comfort greater on a standard issue. This has held true for many years, and continues. All of these are flatter cornering sleds, more like the ZRs of old.

The 2008 Arctic Cat F-Series machines come in four engine sizes and two suspension packages, ’standard” and “SnoPro”. The F5 retails for only $7,399. The F6 goes for $8,699. The F8 will run $9,599, and the F1000 costs a cool $11,249 (gulp!). The F6 Sno Pro sells for $9,499, with the F8 Sno Pro running $10,399 and the top-of-the-line F1000 Sno Pro coming in at $12,099. All of these are offered in black, green or orange. The F8 Sno Pro and F1000 Sno Pro were also offered in a “Nightfire Limited Edition” package during the spring at no extra cost.

With the realignment of model names for 2008, the Yamaha Phazer FX of 2007 is now called the Phazer RTX. The RTX is positioned as the “rough trail performance” version of the Phazer, which has enhanced capability with the addition of Fox FLOAT Airshox in the front suspension and some calibration tweaks to the rear suspension.

Also new for 2008 is the addition of snow skirts between the tunnel and seat area, to reduce the snow and ice accumulation that collected on 2007 versions. Other changes for 2008 include a new snow flap and a fuel tank cover.

The Phazer RTX is fitted with a capable dual-shock CK rear suspension, offering a 20-click compression adjustable rear track shock so you dial in the mogul capability. This, combined with the FLOAT shocks up front, make the light (489 lbs. dry spec) RTX a blast to take through the rough. The rider-forward ergonomics allow for manhandling the sled, enhanced by tall and wide handlebars.

The Phazer RTX can be somewhat cold to ride when the mercury drops, and heavier riders will push the (80 HP) Genesis 80FI to the max, but the torque of the little four-stroker is fun. That’s what this sled is all about, fun. Tight twisty trails and rough trails are where the RTX rocks, a lake runner it’s not. Fuel economy is stunning, as is the reliability and consistency. A free-ridin’, good-timin’ mogul master.

The 2008 Yamaha Phazer RTX retails for $7,599 and comes in Team Yamaha Blue with white and gray accents, or a wilder white with orange accents.

Just like all of the other 2008 MX Z models, the all-new MX Z Renegade gets what amounts to the most comprehensive make-over ever when it comes to a snowmobile re-design with the REV-XP platform. About all that’s left over from last year are the engines, primary clutch, skis and coupler blocks. That’s it. Most every other part and piece on the Renegade is all-new. The REV made history, and the REV-XP has the potential to be even bigger.

With this much re-design, it’s hard to know what to expect from such a radically different sled. Instead of a 136” track length, the Renegades now come with a 137” track length. The number of bars is the same, but with slightly longer spacing between them the length stretches out slightly.

The biggest difference, of course, is the weight reduction. Figure fifty pounds lighter across the board, regardless of engine size. This translates to quicker acceleration, less fatigue after long rides, increased maneuverability, and a sled that simply brings back memories of the smaller, lighter sleds of the past. But, with new suspensions and clean two-stroke motors. What remains to be seen is if the rear suspension performance and engine vibration (800R) has been improved over the early prototypes.

The MX Z Renegades continue their tradition of being the better choice for those who enjoy true cross-country riding, a mix of groomed trails and off-trail riding. The added length keeps the tail in line, adds flotation, and smoothes the ride quality with the longer wheelbase. Only in the tightest and narrowest trails will you notice the added length, to the point you might wonder why sleds with shorter tracks are even made. As far as we’re concerned, the Renegade has THE track length that suits more riders more often.

The MX Z Renegade has a choice of two premium engines, each with class-leading power, crisp, linear acceleration, incredible fuel economy and U.S. EPA certification; the Rotax 2-TEC 800R PowerTEK delivers 152 HP, with the 2-TEC 600 H.O. SDI rated at 118 HP. Both engines give the Renegade the lightweight handling of a two-stroke with the fuel economy and emissions as good as, or better than, a four-stroke. Weight? 430 pounds for the six, 437 for the eight. We’re talking 2.875 pounds per horsepower…….did you catch that?

The 2007 Ski-Doo MX Z Renegade 800 H.O. PowerTEK sells for $9,949, and the 600 H.O. SDI goes for $9,049. Buyers in the Spring could also opt for the X-package option, with high end shocks and more race-sled features along with a low windshield and handguards.

That’s right, a plastic rear suspension from AD Boivin, makers of the SnowHawk “snow bike” and the Expert X rear suspension. Called the ZX2 , the rails and swingarms are all made of a plastic composite material, said to be very robust, very durable and free of “weldings”.

The swingarms and wheels (including four 8 in. (200 mm) wheels on the rear axle) are made from UHMW polyethylene (just like plastic skis), and the rails are made from a very special UHMW composite, with both plastics coming from PPD in Sherbrooke, Quebec.

AD Boivin also indicates the composite construction acts much like a plastic ski in that it has the unique ability to absorb vibrations and improve the ride experience. The composite is also permitting a certain flex on bigger bumps and turns, helping eliminate bad feedbacks to the rider.

Available in five different colors (black, yellow, red, blue and green), the ZX2 will certainly provide a unique and modern look to your sled. Depending on its length, the weight (ready to install) varies between 53 and 56 pounds, which represents a weight saving up to 20 pounds for certain models, and is said to be the lightest aftermarket snowmobile suspension available. It is also claimed to have 50% fewer parts than any other suspension on the market. While AD Boivin’s Expert suspension has 152 parts, there are only 51 parts on the ZX2. Of those 51 parts, 12 are identical bolts.

SnowTech test riders have not been given the chance to ride this latest version of the composite rear suspension, but did evaluate an early prototype several years ago. Denis Boivin came up with the idea back in 1998 and has been working on it, on and off, ever since.
Of interest is the fact this is a two-arm suspension, not a single swing arm like the Expert and Expert X suspension. Curiously, both of the shocks are located side-by-side on the rear arm, with no shock at all on the front arm! This arrangement is likely to afford a great amount of ride quality, with the front arm linked to the rear arm (coupled) to keep it from bottoming harshly. There is, however, a limiter strap on the front arm.

One unique feature is the “Revolver” quick-adjust system, which allows you to quickly and easily change the shock leverage ratio for weight transfer and ride comfort adjustments. The plate at the rear of the suspension has five holes and two pins. Two of the holes are for a weight transfer adjustment; the other three vary the moment of “coupling” between the front and rear swing arms.

Spring preload on the two rear shocks is adjusted using an included wrench in the openings on each rail to reach the preload ring (7 positions) of the springs.

The ZX2 includes two KYB shock absorbers that have a positive sensitive system called “G-Force” technology. This custom valving provides a real dual-behavior to offer comfort for the majority of the ride and an anti-bottoming zone for more security and to suit aggressive rider needs. The first 75% of the shock stroke is comfy, with the remaining 25% of the stroke reserved for anti-bottoming.

AD Boivin also indicates the ZX2 does not require lubrication (grease) like other suspensions, as the composite material has the unique ability to lubricate itself. Another slick feature is that snow won’t stick to or build-up on the composite parts, either.

Pricing for the composite ZX2 starts at $1,199 for a black 121” version, and $50 more for colored ones. The pricing goes up for the longer-track suspensions, to $1,349 for black and $1,399 for colored, all the way up to 162” mountain sleds. You also have to buy the appropriate mounting kit that fits your model, or buy the universal kit at $149. For more details go to www.adboivin.com.

The 2007 Arctic Cat F-Series models have plastic hood screens that are press-fit into the hood at various points; as snow screens up on the front and nose of the sled, and what we call the “knee vents”. During aggressive riding, your knees can contact and knock the screens through the hood, causing them to drop down into the pan of the sled. If you catch them quick enough, you can get them before the secondary clutch (left side) or brake disc (right side) starts to notch the plastic.

The snow screens in the hood don’t seem to come dislodged as often, but busting through some healthy snow you can knock them loose as well. We’ve resorted to trying some silicone glue (sealer) to keep the plastic vents screens in place. If you have to order replacement pieces, be aware that some models use grey ones and some have black ones, so there are a couple different part numbers for each piece. We’ve heard Arctic Cat has changed the vents for the 2008s, with an improved locking design with longer tab, so for now we’re going to assume one could order and install the new-style vents. Instead of buying new pieces, you might want to glue the knee vents in place to prevent the knock-through and having them get chewed up by the drive shaft.

It made sense to use a 4-post primary clutch for the higher-torque applications. Having four flyweights and towers would make the clutch stronger, and each flyweight could be lighter to provide the same amount of belt squeeze. So, Arctic Cat fitted their Jaguars and F-1000s with a 4-post primary last season.

Not this year. Arctic engineers have deemed they will be able to provide “improved clutch calibrations” by returning to the 3-post primary. While this will require a change in flyweight mass (each flyweight will be heavier) to make up for one less flyweight, the F-1000 also gets a 46/40 helix in the secondary for improved acceleration and performance.

While most of us are aware of the EPA requirements to reduce carbon monoxide and unburned hydrocarbon emissions from snowmobiles starting with the 2006 model year, few have heard of, or are aware of the new “fuel tank permeation” requirements. That’s right. If you’ve removed the gas cap and noticed what looks like a “liner” on the inside of your new sled’s gas tank, this is what we’re talking about.

Seems the EPA wants less fuel to “evaporate” through the fuel tank. Uh huh. As fuel sits in a plastic storage device, the plastic actually “breathes” and allows some fuel vapors to escape into the atmosphere. By using better materials, permeation of fuel through fuel tanks and hoses into the atmosphere will be reduced. The larger benefit to the average snowmobiler is how these changes should noticeably reduce the smell of gasoline coming from your snowmobile. That would be nice.
According to the EPA, the permeation requirement should only cost about $10 per machine, which should be offset by fuel savings.

One solution to this problem is offered by GE Plastics - Xenoy Resins. These new Xenoy resins incorporate an inherent barrier material that provides adequate permeation resistance. In simple terms, use this Xenoy stuff in the plastic as you make the tank and you’re done, instead of having to coat an existing tank. It comes in both blow-molding and injection-molding resin grades, and is expected to be used in fuel tanks for lawn mowers, weed wackers, snow blowers, and most personal recreational vehicles. If you’re into making fuel tanks, visit www.geplastics.com and look for Xenoy resin.