The Contact Patch
by Todd Vosper
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We received some great emails during our first month. To those of you who took the time to
write us; thank you! It was great to hear from you and we hope to hear from you again.

First, a couple of questions from Brock, in GA:

Q. Would a manual fan switch be a good idea on a KLR-650?

A. As mentioned on the “About Us” page and in Elden’s “Fuel for Thought” articles, we think
a manual fan switch is a great idea. In fact, I would say it’s Elden’s favorite electrical
modification. There are several methods available. You can add a power lead directly from
the battery (we recommend adding a fuse), and add either a second switch or a relay
(activated by a switched power circuit) to keep from draining your battery should the switch
be left “on”. The fan switch can be wired in parallel with the existing fan circuit so that even
if your manual switch is off, the fan will still be thermostatically controlled. Brock wired his
switch directly from the city light circuit, which is already wired through the ignition circuit. If
you look on the Internet you’ll find a lot of questions about how much load the city light
circuit can handle, but I know there are quite a few KLR’s with heated grips and other high-
draw items running directly from the city light circuit. I would again recommend adding a
fuse. If a short occurs at your manual switch or at your connection to the fan circuit, you’ll
blow your 10A fuse (under your seat) and lose your lights. However, it’s a very simple wiring
solution and I’ve asked Brock to keep us posted. If you ever have doubts about whether the
city light circuit is up to the task of powering your new accessory, use the circuit instead to
operate a relay, and add a new line directly from the battery to provide power. We are
going to wire one of Elden’s KLR’s in the near future using the relay method and we’ll post
the pictures and more detailed explanation.

Q. My biggest hazard isn’t rocks but logs and stumps. Will the stock bash plate be

A. This is a great question, not only because it’s a good topic, but it’s a good reminder to
me that you all don’t ride in Baja, and rocks aren’t the only villains lying in wait for your
engine case. As we’ve mentioned before, one of the best modifications you can make is to
replace your stock drain plug with a low-profile design. Remember however, even a low-
profile plug is capable of snagging something under the bike. As Elden says, the bash plate
would probably be better named a “deflector” plate. The stock bash plate is very good at
deflecting most road hazards away from your bike. One advantage of the stock plate is that
it can flex, and by flexing it will absorb a lot of the energy that would otherwise be
transmitted to your engine. That said, there are a couple of factors that can create a bad
situation for your engine.  The first is hitting a hard, sharp object that produces enough PSI
to cut through your bash plate and into your case. A likely scenario for this occurs when
you bottom out and slam the bash plate against something hard beneath you. The second
factor is where you hit the bash plate. If you strike a hard object across one or both of the
lower frame members, you have a much better chance of avoiding damage. If you are
unlucky enough to strike that same hard object between the lower frame members, the
stock plate is much more vulnerable. Given these two factors, I’m sure it’s possible to do it
with a log or stump but I think it would be quite the exception, not the rule. Maybe I should
stop saying “you may need an aluminum plate if you ride in rocks” and modify it by saying
“you may need an aluminum plate if you ride in conditions where you may impact hard,
sharp objects that can generate enough pressure to threaten your engine case.” I wish
there was a “one size fits all” solution to this problem. What we hope is that you will evaluate
your personal riding requirements, weigh the advantages and disadvantages of each type
of bash plate, then make an informed decision. The fact remains that the stock plate is the
best solution for most KLR riders under most riding conditions.

Here’s one for our DR-650 riders:

Q. What would be the best spring for me? I’m 185 lbs and plan to ride frequently
with my girlfriend (125 lbs).

A. The first question to ask is “How much time will you really spend two-up?” The stock DR
spring is often referred to as too soft. There are two things to be aware of. First, the DR
ships from the factory set at a fairly light pre-load setting. For riders less than 200 lbs,
setting the pre-load at the maximum setting may be all that’s required. Second, the rising
rate of the DR can be deceptive. Although it may seem a little too soft at first, it ramps up
rapidly and gets pretty tight near full compression. In fact, we think the rising rate of the
KLR-650 is superior in this regard. The problem with this deceptive rate (and factory pre-
load setting) is that many riders replace the stock spring with one that is progressive, or
one that is excessively stiff. They may seem ok during initial travel, but as the rising rate
rapidly increases, the suspension becomes overly tight. That leads us back to the original
question posted. If you are going to ride two-up quite often, a new spring is probably in
order. If two-up riding is going to be infrequent, I would recommend increasing the pre-load
and staying with a stock spring. Let’s look at each case. If the stock spring is replaced with
a spring stiff enough to achieve the proper ride height (sag is about 1/3 of the total travel)
when riding two-up, it will be excessively stiff for solo riding. Not only will it be a rough ride
solo, but the rake and trail will be decreased, which will make the steering twitchier. This
results in a very poor set-up if our rider wants to do any off-road, solo riding. Although he
will have lots of suspension travel available, chances are he’ll never use it because the
rapidly rising rate combined with the overly stiff spring will never allow full compression.
There’s a reason for the rubber bumper on your shock. If you are not sometimes
compressing the suspension to full bump, your suspension is not giving you the best
possible ride. Let’s say our rider decides to stick with the stock spring. How will that affect
his two-up riding? Two-up, the bike will sag more than we normally would want; maybe as
much as 50%. But there is an unintentional advantage that is created. With “too much” sag,
the rake and trail will increase. So now when riding two-up the steering will actually be
slower and more stable… maybe not such a bad thing when taking a passenger off-road.
Additionally, that rapidly rising rate on the DR will help keep our two-up riders from
bottoming excessively. And from a practical point of view most riders will use some
discretion when selecting their riding routes with a passenger on board. Assuming our rider
adjusted his pre-load, his solo riding position should be very close to optimal. Let’s recap:
changing the spring for two-up riding will result in the correct sag and rake and trail while
two-up, but probably make for a miserable ride solo. Staying with a properly adjusted stock
spring will result in spot-on performance solo, and the disadvantage of losing some
suspension travel two-up (remember that excessive sag) will be partially offset by the more
stable steering provided by the increased rake and trail. Which all goes back to the first
question I posed – “How much time will you really spend two-up?”
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