Technical Insights
by Elden Carl
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Welcome to Technical Insights!

Our webmaster at "topgunmotorcycles.com", Todd Vosper, has asked me to revive the old
column that I used to do back in the 1990's for "Kawasaki Dual sport News," later called
"Dual Sport News." The goal is to supply you with top quality, unbiased information that
you will not find anywhere else in this business-driven world of ours. I have Todd's word
that as long as our information is accurate and based on sound research, he will put it up.

Summer Warning:

As we've said many times before, the best engine protector for a KLR650 is the stock one
unless you are a rock crusher. It's one of the few that breathes well enough to be used in
the hot summer months. My street KLR and DR650's have no bash plate during the
summer thereby allowing a maximum amount of cooling air to pass over the lower part of
the engine.
What's NEW!
At about the turn of the century, I warned Kurt and Jim Bellach (another KLR650 rider)
about loose balancer chains jumping track due to the KLR650's poor adjustment
mechanism. Shortly after the warning, Kurt's and Jim's engines blew up about two weeks
apart. The remains of Jim's bike are in my shed, and Kurt and I rebuilt his engine after a
good welding repair job on the left side of the crankcases.

Now fast-forward to June 2006 and Kurt's engine again disintegrated. This time due
apparently to a stretched cam chain that jumped track causing the valves to kiss the
piston. I had a good set of crankcases from Conall O'Brian's old 1990 KLR650, so here
we go again. We replaced the front balancer and counter shaft bearings after Vey de la
Cruz tested everything else and gave his approval. We installed top quality everything
inside the crankcases including a low mileage trued and welded crank. I next
transported the finished crankcase assembly to Ron Jensen's place at Pine Mountain
Club in Kern Co., CA. Kurt in turn drove over that evening from his second home in
Avila Beach, CA to take possession of the assembled parts. (Kurt's first home is
Mulege, BC, Mexico.)

I had helped Kurt assemble the complete engine the first time around, but this time "Mr.
G" went solo. He assembled the balancer system complete with a "Jake" lever and
Eagle spring followed by the starter/rotor assembly. After assembling the right side
parts, the top end went on and he was close to being back on the road again.

Kurt called me the other day after completing the rebuild job and reported his new
engine runs very strong, and is quiet and smooth. Good show, Mr. Grife. It was fun, but
let's not do this too often.
Not only is the KLR650 plug too
long, but it's not protected like the
DR650
.
The stock KLR650 engine protector got a
bad reputation for the wrong reason.
Passing rocks have sometimes hit the long
stock oil plug, stretching the drain hole,
resulting in a leak. Various sources
including Dual Star have a shallow plug
which is less likely to get snagged. Rod
Morris and the previous owner of Rod's
1996 KLR650 (Joe Carpenter) have a
combined 20,000+ off-road miles (mostly
Baja) on the best factory KLR650 I've ever
seen and it's always had a stock engine
protector.
On the left is a stock KLR650 plug,
and on the right, an inexpensive,
low-profile plug from N.A.P.A..
The DR650 drain plug is properly
engineered. Not only is the plug close to
the engine, but an aluminum ridge in front
of the plug deflects the rocks that get
kicked up by the front wheel. Additionally,
the optional factory engine protector is
designed to only protect the frame and
bottom of the engine, thereby allowing
cool air to bathe the sides.
If you are a "rock crusher," it's best to
wait until the cool months before you start
covering up too much of the engine; that
is unless shorter engine life is not
important to you.

Kurt Grife's KLR650 Engine Odyssey:

All-around good guy Kurt Grife has about
100,000 miles on KLR650's: We'd like to
say trouble free miles but alas, we must
tell the truth.
Suzuki DR650 engineers dictated a
short oil drain plug, and a cast-in
ridge in front of the plug to deflect
rocks kicked up by the front wheel
The DR650 drain plug is properly
engineered. Not only is the plug close to
the engine, but an aluminum ridge in front
of the plug deflects the rocks that get
kicked up by the front wheel. Additionally,
the optional factory engine protector is
designed to only protect the frame and
bottom of the engine, thereby allowing
cool air to bathe the sides.
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