Brute Force 650 & 650i Carburetor Orientation Changes and Removing the Air-Fuel Mixture Plates

Recently we had the opportunity to help a friend get his quad up and running.  The ATV was a 2006 Brute Force 650i and was in dire need of a thorough carburetor cleaning and air-fuel screw adjustment.  Removing the carburetor's on the Brute Force 650i requires removing lots of plastic body panels, air box, several cables and hoses.

Not long before getting into this 650i project we cleaned the carbs on a 2013 Brute Force 650 with a solid rear axle.  The carburetor orientation was different on the two 650's and it appears that Kawasaki changed the orientation of the carburetors on 2010 models and newer.  That being known removing the carbs on both still requires removing all the above mentioned components, but the newer 2010 and up models is a bit easier in our opinion.

Once the carburetors are removed from the ATV cleaning is basically the same on both orientation types.  While the carburetors are off the Brute Force we suggest removing the air-fuel mixture plugs or the round caps that cover them.  This will allow you to precisely adjust the mixture and tune out any stumbles or hesitations in the Brute Force 650 that are common from idle to 1/8 throttle and idle to wide open throttle.  The air-fuel mixture caps are primarily there for emission purposes and the hope that you'll bring the quad back to the dealer when the symptoms show up.  Both the 2006 and 2013 Brute Force 650 we tuned needed the fuel mixture enriched to remove stumbling at low throttle.

Removing the air-fuel mixture plugs on the newer 2010 Brute Force and up models can be achieved with the carburetors still on the quad (click link to watch how), although due to the different orientation of the pre-2010 Brute Force 650 carbs it requires removing them from the quad.  This video shows how to remove caps on the older Brute Force carburetors.  The air/fuel adjustment plug removal process is the same for both.

When adjusting the air-fuel mixture start by counting the number of turns it takes to bottom the screw out.  Once you've counted the turns they were set on from factory turn them back out to the factory setting and make adjustments at out at 1/4 turns.  Make certain all the adjustments are done identically to both carburetors.  To check the adjustments get the Brute Force 650 up to operating temperature and tune by making 1/4 turn adjustments and then riding it until it runs smoothly again.  When you get the carburetors adjusted to that sweet spot your Brute Force will likely perform better than it ever has!  Everything ATV UTV Reviews