Technical Insights
by Elden Carl
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6/02/11

KLR650 Shrinking Fuel Capacity

The list of problems that I've discovered relating to the KLR650 since March 1990 is
much too lengthy to deal with in a short article. Most of them I've written about in
Kawasaki Dual Sport News, Dual Sport News, multisurfacemotorcycling.com and at
present on topgunmotorcycles.com, run by Major Todd Vosper, a retired Marine Attack
Pilot (AV-8).

The first problem that had to be fixed on the KLR650 was an over dampened and grossly
under-sprung rear stock shock. Stig Pettersson at
Pettersson Pro Suspension
(
info@ppsracing.com, 714 323-5779) fixed that with a one-off Ohlins remote reservoir
shock (the first for a KLR) made out of spare parts in 1992. The proper spring rates took
some testing but the results were worth it. Now available through MMP on this website
are the highest quality and best fitting springs you can buy for the KLR650 stock shock
(1987 - Present).

The second and most important KLR650 defect I discovered in the 1990s was the spring
and "doohickey" breakage problem that accelerated in frequency when the balancer
sprockets went solid in 1996 (pioneering KLR650 world traveler Richard Kickbush of
Canada tipped me off to that one). Good guys like Kurt Grife and Jim Bellach suffered
blown engines within weeks of my warning them about the defective balancer system.  
We fixed Kurt's engine and the remains of Jim's bike are still in my shed. Big Jim, a giant
of a man, now owns and rides 1000 V-Stroms with more than 150,000 miles clocked.

The aftermarket, starting with Jake Jakeman's "doohickey" and later, due to my
insistence, Eagle’s improved copies of the stock balancer adjustment lever filled the gap
until (20 years late) Kawasaki finally produced the toughest and best forged "doohickey"
which retrofits all models back thru 1987. The new thicker bladed lever and the best
spring along with spring inspection port installation instructions are available through
MMP on this website.

The third problem and subject of this article relates to the shrinking fuel supply
sometimes found in KLR's (1987 thru present). I first wrote about this problem in the
1990s, but it continues to rear its ugly head again and again.

Sometime in the mid 90s I ran out of gas about 20 miles from my home. I had only gone
175 miles on what had been a full tank. It didn't take long to figure out that the vacuum
petcock wasn't doing its job. Right or wrong, it seemed to me that overall fuel weight as it
declined due to usage was a factor. The worst aspect of the KLR stock petcock is that
there is no “prime” position, which means that once the fuel stops flowing you can't "turn"
it back on.

My fix back in the1990s was to permanently convert the stock petcock to manual.   "Big
Cee" came out with a nice kit to accomplish the same thing. That kit is now available from
MMP on this website.

In case you don't think this lack of a "prime" position is a problem read on.

I recently set up a KLR650-A that the rider wanted equipped with a stock vacuum
petcock. While test riding the bike I ran out of fuel completely and great grandpa Carl
had to push the damn 400+ lbs KLR half a block to a gas station. It took only 2.3 gallons
to fill the tank which meant there was still a little over three gallons left when the carb
float bowl stopped receiving fuel. With a manual petcock I could have gone another 150
miles at 50 mpg before running out. "Case closed" as Fred G. Sanford would say. The
"G" stands for "gasless" (Note: tipping the bike to the left might get you a few more miles,
but no way does the KLR tank hold 6.1 gallons of usable fuel).

The moral of the story is, unless you wish to run out of petrol in your carburetor's float
bowl while holding three or more gallons of unavailable fuel in your tank, you'd better
"manualize" your "crappy" stock petcock.

By the way, soon after the latest stock petcock failure I put my KLR650 on the Handy Lift
with the stock tank full of fuel. I then attached a long hose to the manual petcock and
turned the lever to the "on" position. When the fuel stop flowing there was slightly over
4.8 gallons in my large gas can. I then turned to petcock to reserve and slightly more
than another 1/2 gallon went into the second smaller can. Since I normally get 50 mpg
with 15/45 gearing, I can go almost 250 miles before I switch over to reserve for another
25 miles.  275 miles beats 130 miles per tank any day. I rest my case.
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