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Blown belts
Q Arctic Cat’s ProCross chassis has been known for blowing belts... what are the best and most effective ways to eliminate this? – Anonymous
A As always with belt issues, the first things to look at are the integrity of both your primary and secondary clutches. Make sure you clutches open and close freely with the springs removed. If there is any bind or slop in the movements, have the clutches rebuilt or replaced. The new 2014 Cat secondary clutch is much better than the original so I suggest anyone running a 2012-2013 stock OEM secondary clutch should upgrade to the 2014 version or another aftermarket clutch.
The second is to make sure your clutch offset, X & Y axis parallelism and deflection are correct. The manufacturer does not give a procedure for Y axis adjustment on the ProCross/XF/ProClimb Chassis, but it can be done with shims under the front motor mount on one side or the other.
The third thing to look at is your actual clutching – make sure your weight, spring and helix combinations are correct and your sled operates in the right rpm range. If your machine is stock, stock clutching works well. If modified, look to the companies that provided the mods for insight into the clutching.
If you are confident that the above are correct and you are still blowing belts, then you could look at upgrading your driveline. We have engineered an entire driveline update which essentially removes the factory engine/jackshaft link and decouples the engine. We have determined the secondary clutch sometimes bends on the jackshaft toward the primary clutch under power which severely affects the parallelism. The engine/jackshaft link on ProCross/XF/M series sleds uses spherical or “wobble” bearings to allow the engine and jackshaft to move together. The spherical bearings cannot always keep the fairly small diameter stock 4140 21 HRC (these numbers are the material and hardness of the stock OEM shaft) jackshaft straight under high power. This problem can be worse with higher horsepower machines. Once the link is eliminated, regular straight bearings can be used. If your sled has power enhancing modifications installed on it, we suggest possibly upgrading the jackshaft, motor mounts and engine brackets as well.
Also the decoupling of the engine from the jackshaft provides some cushion for the belt if the clutches lose control of the belt and then grab again. With the stock link setup, the clutches losing control and grabbing again creates a “shock load” that the belts cannot absorb. Belts are extremely strong in tension, but cannot take a snapping load. With traditionally setup sleds (no hard link between the motor and jackshaft), the motor mounts have always provided a cushion for the belts to reduce the shock load. – Jim Zuccone, Evolution Powersports