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

Primary Clutch Puller Tool to change belt on Kawasaki models: Prairie, Brute Force, Mule, Tyrx, KFX, KVF

On one of our recent fix it videos we performed a belt change on a Kawasaki Brute Force.  Having no repair manual and being a novice to the belt change on the Kawasaki's we ran into a problem when trying to remove the primary clutch.  Some folks claimed that the older belts could be rolled off the secondary clutch.  We tried this method and possibly could have removed it, but then we would still have to install the new belt and take a chance on damaging it or warping something else.  After some research we found a primary clutch puller on Amazon sold by MTC (part#: 57001-1429) for less than $22 shipped.  The puller had some good reviews, but you know the old saying, "You get what you pay for".  So I then looked into making my own puller, but couldn't come close to this price in purchasing the all thread alone.  When the puller arrived I threaded it into the primary clutch on the Brute Force.  A couple turns of the puller and the primary clutch popped right off.  With the primary clutch removed it could be positioned closer to the secondary clutch and the belt slid right off.  The primary clutch puller worked as advertised and there were no signs of damage to the tool.  When something works and it's a good value it gets passed onto our readers.  This video explains how to change the belt on a Brute Force with this tool.  MTC claims the puller works on the following Kawasaki models:
KFX700
KSF700
V-FORCE
KVF750i BRUTE FORCE 4X4i
KVF700
PRAIRIE 4X4
KVF650 BRUTE FORCE 4X4
KVF650 PRAIRIE
KVF400 PRAIRIE 4X4 and 2X4
KVF360 PRAIRIE 4X4 and 2X4
KVF300 PRAIRIE 4X4 and 2X4
KAF620 MULE 4X4 and 2X4
MULE 3010 4X4
MULE 3000  

How does the BRUTE FORCE 650 stack up? Test Review: Comp, Grizzly, KingQ...

Rear Independent Suspision IRS versus Solid Rear Axle SRA comparison

The advantages of a rear independent suspension (i) versus a solid rear axle (SRA).  A solid rear axle can be a lot of fun and there are advantages to both rear suspension types.  This article will explain the differences and what you can expect out of both.

The solid rear axle has been around since the first ATV rolled off the assembly line.  It's tried and true and has some unique advantages over the newer independent rear suspension.  The SRA offers a solid more stable ride and is a top choice for folks who enjoy riding their quad aggressively.  The SRA doesn't load up when quickly spinning the quad around like the independent suspension tends to and is a top choice for those who race their quad.  It also serves as a great utility quad platform where hauling and pulling heavy loads is the ATV's primary purpose.  It is a bit less forgiving on the trail, but defiantly has its advantages.  Less moving parts involved in this setup, which means less to tear up.  The solid rear axle just makes the atv fun to ride.  Unfortunately the SRA is being phased out on the big bore sport utility quads and to own one you'll have to buy used.

Independent rear suspension has been around for some time now in the ATV industry and has became quite popular with folks.  If trail riding is you're primary use for the quad, independent rear suspension offers a superior ride quality.  Unlike the SRA, independent rear suspension allows each rear tire to react independently to the terrain.  Most all independent rear suspensions incorporate a sway bar that lightly mimics the characteristics of the SRA and allows sportier more aggressive cornering, but not near the solid feel of the SRA.  Independent rear suspension setups will cost more when purchasing your quad, but after a 50 mile trail ride you'll be glad you paid a bit more.  More moving parts to tear up in this setup, but manufactures continue to improve on their designs.

Having put many miles on both setups I can say that both get the job done.  It will really boil down to what your major purpose for the ATV will be.  If your in the market for a big bore atv you're only choice will likely be the (i) rear suspension setup.Watch SRA ATV in Action

How to find and remove the air/fuel mixture plugs on the Brute Force 650

Can't find the air-fuel mixture screw on your Brute Force 650?  This article and the attached video will explain how to locate and access the caps covering the air/fuel mixture screw step by step.  The air fuel mixture screw is located toward the bottom of the carburetors, but can't be adjusted unless you remove the caps or plugs covering them.  Suppose Kawasaki really didn't want folks adjusting on these BF 650 carburetors.  We were able to remove the caps with a dremel and boring bit.  It would be difficult to accomplish this with a drill bit due to lack of space and the awkward angle.  Bore into the plug only a 1/8 inch or less, hold a light on the plug and you should be able to see when you break through the cap.  Be very careful not to go to far and cut into the air fuel mixture screw.  After drilling the hole on the first cap we attempted to pull the cap by screwing a drywall screw into it, unfortunately the hole bored wasn't exact enough for the screw to bite into the plug.  We then removed more plug material and eventually were able to remove it with a pick.  Although the carb located on the front cylinder is harder to access we were able to successfully remove the cap with the screw method.  Here is a link to the: How to remove cap from BF 650 carb video.