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Discussion Starter #1
I made a post regarding the sticking left rear shock on my 2005 Brute Force 750. The machine is used for farm work, wood hauling, etc. The reason the shock stuck is because it somehow, got bent (the rod on the inside). I cut it apart and go the spring off of it (with spring compressors). The shock did not get bent due to abusing the machine, racing, etc. I replaced it with a stock shock ($170.00) because other shocks were in the $400-500 a pair range. It's possible the reason the shock went bad is because despite the heat shield on the muffler, I noticed that from idling, going slow, etc. the shock gets hot and it's not really warm here yet, so I can imagine during the summer it has really gotten warm. The BF produces allot of heat and this may be the price of power.
 

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If you have read my posts you will see I am not a fan of using the Brute Force as a farm utility rig, this is just one reason. They are a performance rig for the guys that ride reasonably fast with light loads, and keep the air and fuel flowing to keep the heat down. They are not suitable for routine heavy slow steady pulling unless they are jetted to the rich side to keep the heat down.

What I suspect is that either the shock shaft seal bonded to the shaft from the heat, or the piston and wiper bonded to the tube, or the shock was hot and got wet and sucked water inside then the water froze, and when the suspension needed to give the shaft bent.

This sort of issue is by no means unique to Kawasaki. All the big performance rigs suffer the same sort of problems when used in slow and steady utility work on a farm.

Since you already have the rig, I would build a secondary heat shield for the shock and richen both the pilot and main circuits on both carburetors to reduce combustion heat. It will also make the engine live a lot longer. If you have a good dealer nearby that has sold a boatload of these to farmers and ranchers, they can advise you on the jets to use in your area.
 

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Discussion Starter #3
RCW. I installed a jet kit #409378 ATV jet kit. I followed the instructions for the stock exhaust. The Kaw main jets were 152 and 158. Dyno jet said to put in the DJ 144 in the front carb and DJ150 in the rear and the Dyno Jet needles on position #4. The kit also had new needles and springs and the slide modification. I did this about 2006 and I think due to back firing after a fast run on the road and letting off the throttle, I called Dyno jet and I think they told me to move the needle up one notch (moving the clip down on the needle). I did this because the dealer said this would take care of the trouble overly lean EPA/CARB induced lean running. It took care of the problem. I run Amsoil 0-40 synthetic oil and I don't let it idle as much and I'll consider the extra heat shield. The spark plugs show the motor is running correctly-color. Thanks for the info. (WE are at 900 feet altitude.
 

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I would recommend you bump the pilot jet size. When running slow and working, these engines run on the primary or pilot fuel circuit more than on the main circuit. A lean pilot is great for DEQ, but really hard on an engine because of a lean condition right where the majority of the work and torque is generated during slower operations.

The OEM pilot is a part number 92064 in #38. They usually cost less than $9 each, there are two, and a bit of careful work with a set of tip cleaners can open up a set pretty easily.
 
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