How can you tell what weight of oil is in a shock? One simple method is to compare its flow rate to known weights of shock oil. We do this using a “paint viscosity meterâ€, a small plastic cup with a specific size hole in the bottom. Fill the “meter†with oil, holding the exit hole shut, and record the amount of time it takes the cup to drain. Assuming all of the shock oils are at the same temperature, the lighter weight oils will drain faster, the heavier weight oils will drain slower. You should be able to quickly determine what weight oil is inside any shock by comparing its flow time to that of a known shock oil.
Monthly Archives: September 2006
Yamaha Apex Sleeveless Plated Cylinder Design
…..Yamaha Apex (150 FI) models feature a sleeveless plated cylinder design, where the previous carbureted RX-1 engine had plated cylinders with sleeves. The change is said to improve heat displacement on the higher-powered fuel-injection engine. In addition, the FI version has an oil pressure sensor. The pistons and rings (and connecting rods), however, are the same as the 2005 carbed models.
ACT Drive Secondary Removal
With many of the later model Arctic Cats fitted with the ACT (Diamond) Drive gearbox and secondary clutch, many of you have encountered difficulty when removing the secondary clutch. Some units (not all) are stuck on the shaft, and require some extra muscle to get them off. This is required to perform service on the unit, or to replace the helix and/or spring for elevation/performance changes.
We’re all pretty much used to simply removing the end retaining bolt and washer(s) and having the clutch slide off. Usually. Unlike the older sleds, where the aluminum clutch has seized to the steel jackshaft due to corrosion, it appears in this case the splines in the clutch are not cut deep enough. When the clutch is tightened to the shaft it can cause it to be “press fit†onto the shaft. Careful application of pressure with something like a pry bar on the backside, along with tapping on the end bolt partially threaded in works in most cases, but you need to be careful so you don’t nick up the back side of the clutch sheave.
Arctic Cat does sell a tool for this specific procedure. Contact your Arctic Cat dealer for pricing and availability.
PowerTEK 800 Connectors
Ski-Doo has suggested all models fitted with the 800 PowerTEK engine packages (2005 & 2006) should have di-electric grease applied to the ECM connector during off-season storage to prevent corrosion of the connector. This is the main connector that plugs into the ECM module.
There is a specific procedure to follow here, being that we’re dealing with the main computer box for the vehicle. Contact your local Ski-Doo dealer to have this preventative procedure performed, or to obtain specific instructions and supplies for qualified technicians.
Ski-Doo Spark Plugs
Anyone who owns a new SDI-equipped Ski-Doo is going to need to know the specific spark plugs that are recommended for their sled. NGK BR9ECS, you say? That’s a start; there are different versions of this spark plug, making matters confusing. We’re not talking about the traditional screw-on aluminum terminals and solid terminals, we’re talking different gaps.
The newer BR9ECS spark plugs will have an additional number on them, a “5†or an “8†for example, right underneath the “BR9ECS†on the porcelain section of the plug. This designation indicates the preset plug gap so you use the proper spark plug in the proper engine. Plugs with a “5†indicate the gap is 0.5mm (about 0.20†for those who are non-metric) and plugs with an “8†have a gap of 0.8mm (about 0.30â€). Most all of the newer lean-burn SDI engines will call for the larger gap “8†version. The PowerTEK 800s are less picky in this regard, they can run either without much of any issues. Take a look at the (black and white) specification decal under the hood that lists the EPA data and it should indicate the appropriate spark plug for that particular engine. Ideally, this is the plug that should be used.
According to NGK, one should NOT attempt to adjust the gap on these style plugs, but those who have done so know it can be done with caution. Some dealers are buying their NGK BR9ECS plugs from sources other than Ski-Doo, so they may not be paying attention to the specific gap for each model. It is more critical with the SDI engines than any other to use the right plug.
Why not just an NGK BR9ES? Properly gapped, it should work just fine if you’re in a pinch (and don’t have an ECS). One of the benefits of the ECS design is at wide open throttle (WOT) the shorter electrode of the ECS doesn’t get as hot as the standard ES, helping to avoid detonation on the lean-burn engines.
Damaged RX-1 Spark Plugs
Owners of 2003 Yamaha RX-1s may experience poor performance or ignition misfiring caused by a poor connection between the coil caps and spark plug terminals. The original spring clips used inside the plug caps could cause the coils to not be held securely on the spark plug. This can cause the coil to “notch†the threaded end of the spark plugs, leading to a poor connection and resulting in misfiring.
If you witness deformation of the spark plug ends, or find the coils to be loose fitting on the spark plugs, you can upgrade to the newer style updated ignition coil caps that have a revised style spring clip. Order Yamaha part #8FA-82310-01-00.
Land & Sea Contingency Awards
Land & Sea, makers of the portable DYNOmite dynamometer system, is offering contingency prize money as a proud sponsor of the National Speed Association’s exciting Pro Stock Asphalt snowmobile drag racing circuit. Sleds in the NSA range from 1000 to 1500cc with highly modified engines, making anywhere from 225 to over 330 HP! Combined with the lightweight snowmobile chassis, these rockets shoot down the quarter mile in 8 seconds at speeds of over 150 mph!
The National Speed Association brings together riders from all ovet the United States and Canada to give them a venue to showcase their talents on their high performance rides. NSA is a self-governing organization with its own set of technical and safety rules, developed from the International Hot Rod Association asphalt snowmobile division.
With several veteran snowmobile drag racers behind the NSA program, the goal in 2006 is to promote and maintain as many races as possible. This series will be in its second season in 2006 and will continue into subsequent years given the numerous growth possibilities that asphalt racing offers to both racers and their fans alike.
For more information on qualifying for the contingency prize money, or to read additional details about this up and coming sport, check out the association’s web site at www.nationalspeedassociation.com
Group Seeks Trail
A group in Eastern Newfoundland is lobbying the federal government to bend its rules and allow snowmobiling in a national park.
The Terra Nova Trail Riders want Ottawa to permit a corridor through Terra Nova National Park that would allow snowmobilers to access nearby trails.
It’s illegal to operate a snowmobile inside the boundaries of Terra Nova, one of two national parks in Newfoundland and Labrador.
Robyn Spracklin, who lives in Charlottetown – a community inside the park boundaries – said it’s unfair that she and others must drive for nearly 90 minutes to reach a trail.
“Everyone has to have a trailer, or a big truck or some way to tow their machine outside of the Terra Nova National Park boundaries, and to get to a location where they can go,” she said.
“It is quite costly and time consuming.”
The Trail Riders are appealing for federal permission to cut a 15-kilometre path from Charlottetown to another trail outside the park.
Park Supt. Jewel Cunningham said the park opposes such a plan, citing potential environmental impacts and concerns about disturbances to wildlife and habitat.
Source: CBC News
Public Land Access Pioneer Inducted Into Off-Road Hall of Fame
A long-time champion for responsible access to public lands will be placed into the Off-Road Motorsports Hall of Fame (ORMHOF). Clark Collins, co-founder of the BlueRibbon Coalition (BRC), was chosen for this honor by a unanimous vote of the ORMHOF nominating committee.
Collins started the BRC, a national recreation organization, to counter the growing anti-access efforts of extreme environmental groups and their political allies. His goals were to make the off-road community become “politically significant” and to promote responsible recreational use of public and private lands. One of his “significant” goals was achieved in 1991 when the Symm’s National Recreation Trail Fund Act was signed into law by President George Bush.
Clark served as the BRC’s Executive Director from 1988 to 2006. Under his leadership, BRC has grown nationwide to include over 1,100 member organizations and businesses representing approximately 600,000 recreationists.
Jack Welch, president of the BlueRibbon Coalition said today, “I am proud that Clark has been recognized by the ORMHOF for his numerous and significant contributions to the off-road community. For many years, Clark worked tirelessly to champion responsible use of public lands and to build an organization that could defeat anti-access groups who had targeted our activity for elimination.”
2007 Polaris Dragon – Enter the Dragon
Back when the RMK IQ and Fusion were first introduced two years ago, they were split along body style lines as long track and short track. The Fusion, despite having a-arms, had a big torque motor and not the lightweight cross country sleds the EDGE XCs and Pro-X models had evolved into. Guys always like having the newest and the greatest from a brand, often times even if it doesn’t really match their type of riding or preferences.
Even though there were legitimate issues with the Fusion 900s, the Fusion 600 and 700s that followed for 2006 still were not the RAW sleds that the Pro-X had become. They really weren’t built for the same riders, but the same riders were buying them.
OK, 2007. Polaris dug deep and knew they needed a true performance sled to offer to their faithful. A lightweight rocket ship, with a cross country capable bump suspension. More Pro-X like in capabilities. Doing what they knew best.
To fit this bill, one would need to make it as light as possible yet retain durability. This would mean using a small block motor, not the big torque gorillas that the CleanFire big block mills were. The 600 H.O. was being finalized as a CleanFire engine, and there’s enough room in there to make it a 700 as well…
Enter the Dragon, a limited-build screamer utilizing the sleeker RMK-style hood and bellypan with a conventional (exhaust up front, carbs in back) architecture motor. Gone is the bulk of the Fusion. Instead, a pure-Polaris in the form of a fire-breathing Dragon.
So, how hot is this new 700? It is a quick-revving engine, spinning briskly up to 8250 RPM. It winds up to peak RPM faster than say a Firecat 700, and has a whisker more power on top. Probably three-four horse would be our best guess right now, @ 140+ HP. We’ll see. The midrange pull is said to be 15% stronger than the 600 at 6500 RPM, right where you do a lot of riding.
For those familiar with a Ski-Doo SDI engine, the Polaris CFI is going to be quite similar in operation in that you pull the rope and the electronics do all the work. No choke, with reliable two-pull starts (usually to pressurize the fuel rail more than anything else). Up and down in elevation or temperature, the engine gets the right amount of fuel and ignition advance to match the conditions and fuel being used. A knock sensor monitors detonation, either by poor fuel or heavy loading of the engine, and compensates to ensure maximum durability protection. And unlike the Ski-Doo SDIs, the Polaris CFI system is batteryless. A larger flywheel and ignition changes make this happen.
The CFI injection consists of an injector in each cylinder and one in each side of the crankcase, making it a four injector system. Solenoid-actuated power valves are electronically controlled for accurate and variable opening, maximizing fuel economy at slow rpm rise rates and providing all-out ass-kicking acceleration when the rate of RPM increase is greater.
Polaris indicates their testing has revealed fuel economy will be right on par with the Ski-Doo SDI engines, something we look forward to after the past few years.
The Dragon is a far leaner machine than the Fusion in so many ways. Gone is the adjustable steering post, with its weight and complexity. That’s OK, we like where the steering post is located with its tall wide bars and curved hooks. It just fits better.
Also gone is the heavy steering of the 2006 Polaris IQs. A bunch of time was spent on getting the steering effort nailed down, with the skis mounted a bit further forward on the spindle to reduce the steering effort, basically a result of the new cast spindles in 2006.
So the Dragon is just an IQ with a 700 instead of a 600? Oh no. The Dragon gets the RAW treatment, stripping away all unessentials to make it light and purpose built – to go fast. Sure, you can strap on some bags if you wish, but the showroom appeal of this sled is meant to be RAW, all the way.
In this respect, the rear of the sled looks rather unfinished. Maybe a bit too RAW for our liking, but air don’t weigh nothin’, now does it? That’s the point. The dry weight spec of the Dragon is 476 pounds. In the day of heavy EPA certified sleds, here is one that is just as light as any of the best cross country 2-strokes, and is EPA-compliant. Yes, you can have your cake and eat it, too.
Ride Impressions
A 140+ HP EPA compliant 2-stroke with trick shocks that comes in at only 476 pounds? The true bump sled is back in the Polaris line. This is as close to a Pro-X as we’ve seen for a few years, and those who prefer that kind of calibration know who they are and have been hoping for this sled. Why we didn’t get it two years ago remains a judgment call, but we’re happy it is here now.
We were told 2-strokes would get heavier in order to meet the EPA regs, and while some have, this one is not. This is still a true lightweight, over the snow vehicle that is compliant. The fuel economy and range are what they should be, and of course the Dragon has the push-button reverse that we all now take for granted (until you hop on a sled without it.)
We didn’t get a chance to run the Dragon alongside a Firecat, but we can tell you there shouldn’t be much difference here – rider weight and set up should more often be the difference, but we’ll see. The Dragons we’ve sampled sure seem like they should deliver on their promise of 140 HP.
What really makes this sled unique are the Walker Evans “Needle” shocks, remote reservoir clicker units from the race department. The tuning needles provide great latitude in calibration, allowing maximum tunability and adjustability as well as extreme durability. The Polaris calibration guys were giddy about what they could do and have done with these shocks, and the sled responds in kind with a balanced performance envelope that is appropriate for the intended crowd. It is not harsh in any respect, but it is not soft in any respect, either. It is compliant when need be and capable when need be, and once you get the preload set for your weight the shock valving can be dialed to your liking. Very sweet.
The ease of steering is a nice change from 2006 models and the ride of the rear suspension is probably the best from Polaris for this segment. The most noticeable thing we detected was a lack of precision handling when it came to initial turn in. The Dragons we rode just didn’t have that planted railing feeling one gets from other sleds, but remember the steering was very light. We look forward to some calibration time to see what we can end up with (yes, one is on its way). Sno Pros and X-Packages have just met their match.
The 2007 Polaris Dragon 700 is very limited in supply and retails for $9,599.





