Maine Rail-Trail Correction

In the last issue we told you about a section of former rail line that was supposed to become a rail-trail, but the state had been outbid by private investors. We’ve now learned that the state has since purchased this property, according to David Soucy, Director of the Bureau of Parks and Lands in Maine. This consists of a 32.5 mile stretch between Houlton and Presque Isle and a 6 mile section between Mapleton and Washburn. Thanks go to Stephen Mitchell in Yarmouth, Maine for alerting us to this new development.


FOX FLOAT Airshox Q & A

Fox has provided some Q & A to common service questions they get regarding their innovative FLOAT Airshox. Now that these lightweight shocks are being offered on more and more sleds right from the factory, we thought it would be helpful to share this tech information about the shocks to help you better understand what is normal and what to be looking for. Like all high-pressure gas shocks, the FLOATs will require disassembly and servicing to maintain their performance characteristics.

First, you should monitor the air pressure at least once every other month and you should perform air sleeve maintenance once a year. Also, they should have a complete rebuild and oil change every 3,000 to 5,000 miles. Complete service should only be performed by a trained technician as it requires specialized tools and knowledge, just like traditional FOX shocks.

Question: There is a slight amount of oil at the air sleeve/body cap joint. Is there something wrong?
Answer: No, the air sleeve threads are lubricated with light grease to make disassembly easier. Sometimes, a slight amount will ooze down the air sleeve. Simply clean the air sleeve and body cap. Keep an eye on the air spring pressure to make sure it remains steady.

Question: Is it normal for oily dirt to build up at the FOX Samurai wiper?
Answer: Yes, this means that the wiper system is working properly. Periodically wipe the oily dirt from the Samurai wiper to keep it clean.

Question: There are small dings on my aluminum impact body. Will this cause an air leak?
Answer: No, the air seal occurs on the inside of the air sleeve only. Small dings on the impact body over time are normal and are nothing to be concerned about. However, big scratches or dings in the impact body will allow water and dirt contamination into the air sleeve that could lead to a long-term air seal failure. In the case of major scratches or dings in the impact body, it is best to replace it.

Question: Will I have to adjust my air pressure when I go up in altitude?
Answer: No, the air pressure in the air sleeve is not affected by changes in altitude

Question: What about the damping in this shock?
Answer: This shock uses the same proven velocity sensitive, oil damped valving arrangement that is used in all FOX Racing Shox shock absorbers. The valve code or calibration has been carefully tuned for each application to give the best all-around performance over a variety of conditions.

Question: The air pressure in my shock absorber is different every time I measure it. What’s wrong?
Answer: First be sure that the suspension and shock absorber is fully extended by jacking up the vehicle by the frame so that the skis are completely unloaded and have no weight on them. This is the “home” position for measuring pressure. Second, every time you thread on the pump to the shock, the pressure reading will go down slightly as the gauge fills up. This is typically between 2 and 5 psi.

Question: My shock absorber leaks air slowly over time. What’s wrong?
Answer: There are three possible leak paths. To determine which one is the culprit, remove shock from vehicle, charge the air spring pressure, and submerge the shock in a sink or a bathtub. If the air bubbles are coming from the air filler valve, replace it (FOX part number #802-00-001-A). If the air bubbles are coming from the body cap/air sleeve joint, replace the body cap O-ring (part number #029-01-135-A). If the air bubbles are coming from the bottom of the air sleeve past the FOX Samurai wiper, clean the air sleeve and replace the air piston seal (part number #036-01-014-A) and the two Air Piston Slyde Rings (part number #002-00-012-A).


Summit Running Board Reinforcement Kits

With the introduction last year of the very open running boards on Summit Liquid-cooled models that were designed to reduce snow and ice build-up in deep powder, some very aggressive or heavier riders found the running boards could possibly sag or bend while riding in extremely rough conditions.

Ski-Doo now offers a running board reinforcement kit to strengthen this area of the running board, as well as triangulate the foot well area for improved strength. Order part #861 804 300. This kit contains all necessary reinforcing parts, including rivets and instructions. The kit will add a slight amount of weight, but the running board will be considerably more rigid.


MonoShock RA Remote Cable Adjuster

Do you turn the remote adjuster dial on your 2005 Yamaha RX-1 with the MonoShock RA rear suspension but sense no change in suspension compliance? The cable could be broken!

The remote cable adjuster and protective rubber boot found on the 2005 Yamaha MonoShock RA rear suspension can become damaged during riding. To prevent this occurrence, Yamaha is installing a “RA Protector Kit” into all 2005 models fitted with this new rear suspension. This kit consists of a new cable and boot assembly, a new steel protector, and mounting hardware. Owners of these units should contact their dealer to schedule installation of this kit.


2004 SDI Fuel Starvation

There have been a few reports of 2004 Ski-Doo models fitted with the 600 H.O. SDI engine package experiencing fuel starvation under hard acceleration. Some of these instances have been caused by the fuel pickup at the rear of the tank being installed backwards or too high in the tank. In some cases, the machine would momentarily act like it was running out of gas, even with 1/4 to 1/3 of the fuel remaining.

If your 2004 SDI 600 acts like this, an inspection of the fuel pickups should be performed. The rear fuel pickup is at the end of a length of fuel hose positioned at the rear of the tank. The pickup should lie flat on the bottom of the tank, so the angle at which the pickup is installed into the fuel line is critical. Adjust as needed.

Also, the length of the fuel line to the back of the tank shouldn’t be so long that it lets the pickup ride up on the rear wall of the tank. This fuel pickup line is only available as an assembly due to the critical nature of indexing the pickups to the fuel pump. Replace this fuel line assembly if needed to keep the pickup laying flat on the bottom of the tank.

If the rear fuel pickup is installed backwards, no fuel can be drawn through it. This can be identified by inspecting the fittings on top of the fuel pickup. The exposed fitting (opposite the fitting where the fuel line is attached) should be smooth with no “barb” or “nipple” exposed. If the exposed fitting does in fact have a barb or nipple at the end to attach a fuel line to, it is installed backwards.

Proper indexing of the pickup assemblies to the fuel pump is critical, so be sure to accurately align the arrows of the fuel pump with the arrow on the fuel tank. Refer to the appropriate shop manual to ensure proper positioning of the fuel pickups.


Yamaha RS Error Code “84”

Some of the 2005 Yamaha RS models (those fitted with the three-cylinder 4-stroke 1000) may falsely activate the Throttle Override System (TORS) and indicate an “84” error code in the tripmeter/odometer display (along with the warning indicator and engine icon).

We experienced this on our 2005 RS Vector, and a number of Vector owners also reported this occurrence. Yamaha indicates this can be caused by the ignitor unit’s settings not responding correctly to certain normal operating conditions. A mismatch, of sorts. The TORS system can activate when it is not needed, in situations where the throttle operation may be normal. The sled will act like you momentarily hit the kill switch (safety stop switch), where ignition is cut briefly, as the TORS falsely senses faulty throttle operation (TORS compares the position of the throttle at the carbs to the position at the handlebars, and if it detects the throttle is open at the carbs but closed at the handlebars it cuts the ignition).

Yamaha dealers have been instructed to replace the ignitor unit on machines that experience false activation of the TORS system. If your 2005 Yamaha RS model experienced these symptoms, contact your local Yamaha dealer.


Piston Wash – How Much?

2-stroke engine tuners know that observing the amount of piston wash on the piston dome is a very accurate indicator as to the best fuel-air mixture for maximum power production in competitive situations. These small “clean areas” on top of the pistons, located where the fuel enters the combustion chamber at the transfer ports, are indicative of the amount of excess fuel entering the engine. The smaller the “wash”, the leaner the fuel-air mixture.

How much is the perfect piston wash? The engine builders at Black Magic Racing tell us we should keep two important items in mind when we are looking at the wash on top of the pistons. Based on their experience (with Suzuki engines) the engines with flat top pistons can run less wash and not lose performance or detonate. The domed pistons need to run more wash than a flat top piston in order for the engine to run at peak performance.

Flat top piston wash, such as in a ZR 600 or ZR 500, at peak performance, will be the size of the nail on your little finger. You can get slightly smaller than this, but then the performance will begin to go down hill and the detonation point gets closer.
Domed style pistons need to have a wash the size of the nail on your thumb or slightly less. Running a ZR 800 or ZR 900 with a wash much less than this will lose performance. The 8’s and 9’s, along with the F6 and 7’s, will begin to lose power if the wash gets much smaller or becomes non-existent. The reason these engine just lose power and sometimes not even detonate, is due to the timing curve which is much milder than the 5’s and 6’s were back in ‘98-99.

Remember, the amount of piston wash explained here is based on regular octane fuel. Running race fuel, if you have the compression to burn it, will allow the size of the wash to become less through jetting and not lose as much HP. If you are into getting the most out of your engines, use this rule of thumb to keep enough fuel thrown at it and avoid the burndowns.


2005 Arctic Cat M-Series Bulletin

Arctic Cat has alerted their dealer network regarding all 2005 M-series sleds. It has been determined that there are two conditions that need to be addressed on the 2005 M-Series snowmobiles. As you may already know, there is a possibility of moisture having entered the gear case. If this condition exists and the service work is not performed, damage to the gear case components may occur. Second, the current drive shaft cap screw might break due to excessive vibration if the snowmobile is operated in hard-packed snow conditions.
Arctic Cat dealers have been instructed to contact all owners of record to remedy these situations. The Diamond Drive gearbox will be removed, drained and flushed, a new seal installed and new lube added. Also, a new driveshaft cap screw will be installed.


Mach Z 1000 Clutching

The 2005 Mach Z was delivered with the TRA clickers set at #6, and this allowed the mighty twin to over-rev. Most riders simply turned the clickers down to #1 or #2, and while this tamed the peak operating RPM it tended to cause too much mass being thrown at the lower shift ratios, depending on conditions.

One of the hottest set-ups for the 2005 Mach Z was to install a set of lighter aluminum arms with an adjustable pin kit, typically set to 22 grams. Many shops were doing this using the Dalton Aluminum TRA arms for the Mach Z, along with the Dalton adjustable pin kit, while others used a Thunder Shift Kit from Fett Brothers Performance. This allowed them to run the stock spring in the primary and all of the stock secondary components. Set the clickers so you spin the twin at 7850 RPM and hang on. Tight.

For 2006, Ski-Doo tells us all of their 1000 SDI models can be enhanced for optimum performance and top speed. Mach Z and Renegade 1000s can install a 25mm set screw (part #206 262 599) into each TRA pin, and set the clickers to #2 or #3 to reach the target operating RPM of 7850.

Summit models used at sea-level (below 2000 feet elevation) can install a long threaded pin (#417 222 595) into each arm along with the 25mm set screws mentioned above. Again, set TRA clickers to # 2 or #3 to reach the target 7850 RPM


1000 SDI Updates

Last issue we told you about updates for the 2005 Summit 1000 models; Ski-Doo has now informed their dealers of additional updates to be performed on 1000 SDI models, including most Summit 1000s and all Mach Zs. These machines will receive enhancements aimed at improving both performance and reliability.

Almost all of the 2005 SDI 1000 models are to get an ECU calibration update, a fuel pump update where the mechanical fuel pump is replaced with an electric one, the cable for the electronic power vales will be updated, and several pyramidal frame bolts will be updated. Mach Zs also get an EGT sensor placed in the exhaust canister.

The ECU updates reflect the latest software calibration for controlling the fuel injection, ignition timing as well as power valve operation. The fuel pump update should eliminate issues of fuel starvation before the fuel tank is empty. The E-RAVE cable update is in response to the inside lining of the cable coming out and restricting or breaking the cable. Six pyramidal frame bolts are also replaced; the new ones have locking patches to keep them from coming loose. On Mach Zs, a temp sensor is placed into the exhaust canister as the latest ECU calibration now requires this additional input.

A small number of 2005 Summit 1000s are excluded from this procedure, so check with your dealer if you are unsure if your machine is affected. Otherwise, owners of record should have been contacted to have this service performed.