Liberty 600 H.O. CFI You guessed it, a CFI (CleanFire Injection) version of the popular 600 H.O. engine. This is still a “conventional” layout,...

Liberty 600 H.O. CFI
You guessed it, a CFI (CleanFire Injection) version of the popular 600 H.O. engine. This is still a “conventional” layout, with the intake on the rear and the exhaust up front, but it works. This fast revving engine makes peak power at 8250 RPM, up to 125 HP, despite a lowered exhaust valve that also improves the low end power, enhances fuel economy and overall running quality with reduced (again) emissions. Compared to the carbed engine, the midrange is 10% stronger (7500-8000 RPM) and peak power 5 HP greater. Fuel economy? Polaris claims they’re equal to the Rotax 600 H.O. SDI.

This is a 4-injector system, with an injector firing into the cylinder and one firing into the crankcase, right inside of the reed cage placement. The result is emissions 43% cleaner than the industry baseline. A full compliment of auto calibration sensors keep the system spot-on, along with a DET knock sensor for safety and fuel quality issues.

A larger flywheel and ignition components allow for the battery-less CFI. The PTO end is larger, as is the bearing and clutch taper. The water jacket is redesigned to improve the cooling system, and a new airbox helps to improve performance.

Liberty 700 H.O. CFI
This is an all-new engine, as the 755cc engine from last year is gone. Take all of the new stuff from the 600 H.O. CFI (above) and apply it here as well. Larger pistons (81mm vs. 77.25mm) and a longer stroke (68mm vs. 64mm) turn the 600 H.O. into a 700 H.O. This is also a fast revving engine, making peak power (140 HP) at 8250 RPM. It has the same injector placement and sensor array, so it is fully auto-adjusting and runs good everywhere. Power is 20% greater than the 600 H.O. at 5000 RPM, and 15% stronger at 6500 RPM. According to Polaris, it makes 4 HP more than the Arctic Cat F7, but is faster revving, and is only 2 HP shy of the (2006) Rotax 800.

This is the true heir to the Liberty 800, with 3% more power at 8000 RPM and a much broader over-rev (flat power past peak). It actually makes 5% more power at 5500 RPM than the Liberty 800. Our testing of this model indicates it is a very smooth engine with linear power delivery, easily stronger than the 600 H.O. and right on par with what we’ve come to expect from Arctic 700s. About time.

550 Fan Cooled Upgrades
The 550cc fan cooled engine has been upgraded for 2007, now fitted with cooler-running Nicasil cylinders that also improve durability. Tighter tuning calibrations have improved fuel economy and reduced emissions by 30% (HC) and 50% (CO). It all adds up. Performance is improved as well; more pulling power, better low end torque and less belt burning, along with more top speed.

IQ Chassis Expansion
Wow, it must have taken some hard swallowing and head shaking, but they did it; the Fusion name and body work is gone for 2007. All of their IQ models are now fitted with what we consider to be the far-better looking RMK skin, now appropriately called the IQ chassis. Last season the shortest track length you could get with a 2-stroke was the Classic 700 at 128”, now there are a host of 121” IQ sleds fitted with 2-stroke and 4-stroke engines, and plenty of (good looking) color options as well. The “orange” IQ is really stunning on the snow, the black Dragon looks (and is) pretty mean, and we’re always a sucker for red and black when it comes to Polaris. Thank goodness they came to their senses.
Too bad they didn’t figure this one out two years ago. Whoever decided to make two bodies for the same chassis was probably shown the door, as they could have had this “look” at that time, but it was more the early introduction of the 900 that did so much damage to the Fusion name and image. In this business, image is reality, and regardless of how well the 2006 Fusions worked, the damage had been done. We know it was tough to do, but hats off to Polaris for making 2007 the year of the IQ. With the new CFI engines they’ve got some excellent sleds.

Fixed Steering Posts
How can Polaris walk away from their innovative Rider Select adjustable steering? They’re not; well, on some models it is gone, namely, the performance 2-strokes and IQ RMKs. It saves five pounds of weight! Polaris found too many riders were setting it too far forward in the wrong conditions, screwing up the handling and then complaining about it. On the hi-performance models where weight is so critical, is has been removed and the end result is just fine as the handlebars are now where they should be for most riders, and the arc they turn in is more pleasing as well for most. While we thought it was a cool idea, most everyone has figured out rider-forward is a good thing and hardly anyone was using the down and back settings.

IQ Ski Relocation
Most (if not all) of these IQ models have skis that are in a new mounting position and a softer ski rubber that reduces the heel pressure, along with a “shaved rear keel”. Why? To decrease the steering effort. The revised skis are moved 3/4” forward and 3/4” higher on the spindle, and you really notice it on hard packed trails. In side-by-side testing of 2006 and 2007 models, the difference in steering effort it is quite profound, and initial turn in (once it bites) is quicker. We’d still like to see more bite from the ski and carbide combo, but this should be easy to fix with new runners.

Series 5 RMK Tracks
The Series 4 tracks were perhaps the best deep snow tracks in the biz, and now we have an even better track that weighs up to 7.5 pounds less! A new 155” track length replaces the 151” length (and 159”), and the Series 5 also comes in a 166” x 2.4” version. Larger pitch (we assume 3”) spacing improves the “bite” in deep snow, and along with the longer window openings reduce weight and improve hyfax cooling. Center holes (square, not round?) also reduce weight, and on the 166” models a center-drive helps to prevent ratcheting.

Take a look at the new RMK models (and the Dragon) and there seems to be something missing from the rear of the sled. Mountain riders hate weight, so Polaris did them a favor and got rid of even more. RAW RMKs have a stunning 25 pound weight reduction; from where? Tunnel; 3lbs. Cooling system; 6 lbs. Footrest; 1.5 lbs. Steering system; 5 lbs. Track; 6 lbs (average). Rear suspension; 2 lbs. Misc. components; 1.5 lbs.

Like the 2003 Firecats, the outer rear idlers are gone (said to improve sidehilling by allowing the track to bend slightly and reduce rider fatigue), with only the two inner rear axle wheels intact. The radiators have been removed, and the tunnel cooler is now a stressed chassis member. Polaris claims the new cooling system can reduce the weight of ice in the tunnel by up to 40 pounds!

Detail changes include 1.5” taller handlebars, footrests that are 2” back for a flat standing surface, running boards that are 2” wider at the rear (great for feet, but we’ve all seen deep bottomless powder conditions where this is a bad thing) and 1” holes in the running boards to allow snow and ice to drop through instead of building up. Some models (Snow Check only) get Walker Evans Air shocks for a plush ride with big bump control. Bottom line, RAW RMKs are lighter weight and easier to ride. The battle for western dominance is going to be very intense.

RMK Gripper Skis
It seems like every year there is a new ski design; 2007 is no different, as IQ RMK models are fitted with new “Gripper” skis. They are 24% wider (inches, anyone?) and claim to be the lightest in the industry. A re-shaped keel helps to reduce steering effort while maintaining bite, and there is a “traction” feature on top (what does that mean?)

Lightweight TEAM Roller Secondary
Most Polaris models have been fitted with roller secondary clutches from TEAM Performance for a few years now, and for 2007 there is a lighter version called the “LWT” TEAM clutch. This latest roller clutch is a full 15 ounces lighter (nearly a pound) and in the critical area of rotating mass, it amounts to (effectively) a several pound weight reduction in terms of accelerating mass and performance. This makes machines so equipped more responsive and quicker to accelerate. Making copious power is one thing, but accelerating all of the mass and getting the power to the ground is a whole different animal. Polaris has long been known for efficient power transfer, and this upgrade just sweetens the package.

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