The Contact Patch
by Todd Vosper
Copyright © 2006 Top Gun Motorcycles. All rights reserved.  Distribution or publication of this document (electronic or otherwise)
is prohibited without the express written consent of the author. For more information or to request permission to publish this
document, please see our
contact page. For information on our pledge to maintain your privacy click here. To learn more about
your friends at Top Gun Motorcycles, read about us
here.
Top Gun Motorcycles
Contact Patch
09/01/2008

Q. I'm a 215 lb rider and normally ride solo without much gear. However, from
time to time, I take longer trips with 50-60 lbs of gear. I want to upgrade from
my stock spring; which spring should I buy?

A. This is probably the most common question/situation we get asked about at Top Gun
concerning springs. A rider normally does most of his riding in one configuration, but
every once-in-a-while, he or she loads up the bike or goes on a trip two-up. Which
spring to choose?

If you look at our
spring table, you'd see the situation above seems to dictate a 6.6kg
spring for normal riding, and a 7.4kg spring for the longer trips. Of course, the perfect
solution would be to have both! However, that's generally not possible for most of us. In
situations like this (choosing between two springs), I tend to go with the spring that will
work best for the majority of riding. If the rider spends equal amounts of time in these
two different configurations, I favor the lighter of the two springs.

Let's first look at the situation where our rider decides to go with the 7.4kg spring. For
the occasional big trip, he should be able to achieve proper ride height and a good ride
for the combination of gear and weight. However, for the majority of riding time, he'll
have to put up with a harsher ride than necessary and won't be stroking through the full
suspension range.

On the other hand, if he selects the 6.6kg spring, he'll have the proper spring for the
majority of his riding. On his longer, heavier trips, he will not be able to achieve proper
ride height, even on a preload setting of 5. The "silver lining" to this situation is that
generally, most riders don't tackle the same level of terrain when they are loaded down
heavily. This normally mitigates the loss of suspension travel caused by excess sag.
Additionally, being lower in the back end will increase rake and trail to some extent,
which will help stabilize steering - not a bad thing when off-road and heavy. Finally, the
rising rate of the KLR650 will help keep our rider from bottoming except on the hardest
hits (based on the rider's typical terrain and riding conditions). If you ride exclusively on
reasonably-maintained dirt and gravel roads, your hardest hits will be different than
Johnny Campbell's.

The KLR650 has a very nice rear suspension rate. In fact, it is so cushy during initial
travel, that many riders get the false impression that the rear end is too soft. As
explained by some of the same folks who we consulted when designing our springs
(see
Sep FFT), the goal is to have the suspension occasionally and lightly bottom on
the hardest hits. If the suspension never bottoms, you are giving up travel and living
with a stiffer ride than need be.

2008 KLR650 UPDATE!

Well, the oil burning bug bit our KLR650 too! We track our oil consumption religiously,
and our 2008 was burning one liter every 833 miles! To make things more interesting,
we limit our RPM (cruising) on the highway to a maximum of 5000 RPM - we certainly
weren't the "high RPM riders" that Kawasaki has pointed a finger at before. Add to that,
we don't lug the engine nor to we over-gear the final drive.

We will post a more in-depth description of our experiences with this problem in the
future, but wanted to pass along what we'd found with our bike. Kawasaki kindly
explained to us that anything around 1000 miles to a liter was normal and all was well
with our bike. Good timing too - the warranty was about to expire. However, our
experience with the KLR specifically and motorcycles in general led us to believe that
this consumption was definitely not normal. For instance, our 2004, with over 12,000
miles on the clock, goes over 15,000 miles on a liter of the slippery stuff! Again, the
bike is never geared above 15/43, never lugged, and never run at sustained speeds
above 5000 RPM.

Master mechanic Vey de la Cruz agreed that we were experiencing excessive oil
consumption. We took the 08 to Vey and asked him to inspect the cylinder, piston, and
rings. Although we suspected rings, it turned out that our cylinder liner was oval!! And
to add to our surprise, a fellow KLR rider had an 07 in the shop at the same time with
the same oval cylinder problem.

We don't want to steal the thunder of our upcoming article describing our "ordeal" and
subsequent fix in detail, but did want to pass along this finding to our fellow 2008
owners. To our knowledge, this is the first 08 we've heard of that has been taken to an
independent mechanic for evaluation of the oil burning problem. We keep hearing rings
from Kawasaki; we just hope that this liner problem isn't the real cause for other riders
who think they've solved their problem with a dealer installation of new rings.
What's NEW!