Owners of 2003 and 2004 Yamaha RX Mountain sleds are encouraged to update their machines to the 2005 model specifications. Applying the 2005 model specs to the 2003 and 2004 models will minimize shift RPM loss at higher altitudes and provide better overall performance. Basically, the sled will run... Read more

Does your Ski-Doo 600 SDI foul spark plugs during warm-up? Or, does it surge excessively when the pipe is cold during acceleration? Ski-Doo has made available a revised ECM program for those 2004 600 SDI models and 2005 MX Z 600 SDI Renegade models that exhibit these symptoms (other... Read more

One corner that gets cut by many tuners involves the re-use of many of the hardware parts (nuts, bolts, cotter pins) when performing clutch service. Many of these smaller fasteners are specified for replacement during re-assembly. Do you know why? Just image what happens when a re-used cotter pin... Read more

Several speed shops that modify Arctic Cat EFI models have started using a small “black box” available from Advanced Performance in South Haven, Michigan. This small electronic device can add fuel to the EFI mapping, presumably by increasing the duration of the injector timing. It can not, however, remove... Read more

Checking the oil level on these new four-stroke Yamahas requires several specific steps to obtain an accurate reading. Failure to follow the proper procedure can result in a false low oil reading, which may in turn cause you to add oil when you don’t need it! To properly check... Read more

Since Bombardier Recreational Products makes so many different models of what may appear to be very similar sleds, we have found it most helpful when communications with just about anyone regarding a specific machine to include the Ski-Doo 4-digit model code in the correspondence. This will be most helpful... Read more

As the length and lug height of mountain tracks increases, the clutching requirements of the machine also change. This is especially true if you have a working combination and install a more aggressive track. The added length and height works the engine and clutches harder, as the torque feed... Read more

Arctic Cat 900 twin engines fitted with carbs come with Mikuni rack style flatslide (TM-40mm) carburetors. These carbs have an airscrew and a fuel screw, both providing adjustability to the low speed circuits. The air screw is located to the left side of the mouth of the carb, and... Read more

For all of you former two-stroke riders who now have a four-stroke parked in the garage, ask yourself this; do you have a smart charger attached to the battery of your sled, right now at this moment? Or, do you attach a smart charger every month or so to... Read more

If you’ve got a 2004 Arctic Cat 700 EFI (Firecat or Sabercat) make sure the ECU has been reprogrammed! This enhanced software makes a big difference in terms of fuel economy and overall performance. Most noticeably is the improvement in the 30-35 mph range, where the machines were originally... Read more