Top Gun Motorcycles
Technical Insights
by Elden Carl
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01/02/2008

KLR650 Balancer System

We commend Tim Carrithers of “Motorcyclist” magazine (Dec 07) for printing John Gorman’
s long overdue and scathing letter concerning the poorly engineered balancer system in
the KLR650.  “Motorcyclist” is the first major magazine to address the problem, but alas,
they were mislead by Kawasaki Service and inadvertently passed incomplete information
along to their readers.

The fact is that the balancer adjustment lever (doohickey) is only part of the problem.  
The remainder of the problem concerns the spring that adjusts the lever.

Both the factory and after market springs are breaking, and when they do, they can cause
huge problems at adjustment time.  If the spring is broken and you loosen the adjustment
bolt, the weight of the chain can loosen the lever instead of tightening it.  Since there is no
way to inspect the spring (without removing the dyno and balancer covers) to ascertain its
condition (broken or at coil bind), you ultimately could be in real trouble.

The factory also neglected to tell Mr. Carrithers that the new bullet-proof 2008 forged
doohickey fits all previous models of the KLR650.  Obviously they would rather have
Eagle or Sagebrush on the liability hook when the system fails, as Kawasaki has the most
to lose.


There's a delicate balance to be reached when choosing or designing a proper balancer
adjustment spring. A heavy spring stretched far enough to provide more adjustments
before reaching coil bind may place too much stress on the idler shaft and its needle
bearing. Too light a spring may not tension the chain properly, especially as it nears coil
bind, thereby accelerating balancer system component wear. The 2008 KLR650
addresses this balance in a peculiar way: the spring is heavy (stronger and longer lasting)
but so long (in an attempt to minimize spring preload) as to provide only one or two
adjustments before reaching coil bind. From then on the chain will become looser and
looser until it either jumps track or causes excessive wear to all balancer components and
the left crankcase.  Since you can’t see the spring, you won’t know what’s happening.

Fortunately there is “NOW” a fix for the doohickey dilemma but it’s only available from
MMP on multisurfacemotorcycling.com.

The “fix it” kit contains the following:
  • An MMP-supplied factory 2008 forged doohickey.
  • A selection of 3 custom-made, top quality extension springs of varying length
    specifically designed to provide good adjustment length without excessive preload.
  • A Wexman/Carl inspection port kit which facilitates the simple installation of a spring
    monitoring peep hole in the inner cover.

We gave the aftermarket the inspection port specifications when the levers first came out
but they failed to grasp its importance.  As a result, most riders with upgraded levers have
no way of easily monitoring the system (we know of 3 broken aftermarket springs).  

There is trouble ahead for some of those who attempt to adjust a lever not pulled by a
spring.

Jay Bass has dodged the exploding balancer disaster twice.  His 2003 KLR, which died of
a failed mechanical seal, had a broken aftermarket spring and a very loose and noisy
balancer chain. His 1995 had a noisy engine due to a broken factory lever.  His 1995 now
has a 2008 super “doohickey” (or what we like to call the totally different 2008 lever,
“Gizmo”), a custom-made MMP spring, and a Wexman/Carl inspection port.  As a result,
his 1995 KLR650 with only 12,000 miles on the clock is safer and better than any new one
you can buy off the floor, including the 2008.

Most importantly, Jay finally has peace of mind.  By the way, Kenny M of “KBM
Motoworks” (kennym_57@yahoo.com) will be doing MMP balancer adjustment kit
installations.  Jay is his first customer and the first rider outside of MMP or Top Gun to
have the new MMP kit installed.

With well over 200,000 miles on KLRs, I’ve had some balancer close calls.  The last one
was a broken aftermarket spring which I found through the inspection port before
attempting an adjustment.  I pulled the covers and rotor, replaced the spring and was
safely on my way again.  With the new bullet proof MMP springs I won’t have to pull covers
very often in the future.

You are correct Mr. Gorman, the KLR650 engine is not bullet-proof without balancer
system, piston and valve gear improvements; but proper set-up of the left side can get it
pretty close.  Avoiding over-gearing and cruising speeds above 5,000 RPM will also help
keep your KLR wheels turning.
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