The Contact Patch
by Todd Vosper
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This is your chance to ask those questions that you always wanted and answer to but either
didn't know who to ask, or were uncomfortable asking. One of the great things about
working with Elden is that he's been around for a while, and he knows some genuinely
interesting and intelligent people in the motorcycle business. If you have a question that
neither I nor Elden have an immediate answer for, I can guarantee that we know someone
For the first installment of "The Contact Patch", I thought I'd cover some of the basic
questions we commonly hear discussed in person and on the Internet. We'd rather post the
questions YOU want answers to, so please email us and we'll post as many as we can.
Q. Do I need an aftermarket skid plate?
A. When shopping for a skid plate or asking for advice, the first question you should be
asked is “where are you riding?” If you don’t hear this, you’re talking to the wrong person.
The KLR stock plate is frequently trashed as being, well, trash. However, it’s a great little
plate for almost all riding conditions. It’s light, it fits well, and it provides more cooling than
any other plate. Now, if you are riding through big rocks you probably DO need an
aftermarket plate. Just remember that you are adding weight and reducing the airflow
across the bottom of the engine. At least make sure the risk of damage where you are
riding is worth it. Probably the best thing you can do regarding damage to the underside of
your engine is to replace the stock oil drain plug with a low-profile plug. As for the DR, the
stock plate is a bit expensive, but fits very well and provides lots of cooling air around the
sides of the engine - though does restrict airflow somewhat to the front. Remember that
summer or desert riding exacerbates any poor cooling tendencies on either bike.
If you are expecting to do a lot of aggressive off-road riding; if you think you are going to
dump the bike from time to time; or as mentioned earlier – if you are riding in rocky terrain –
you may be better off with a heavier plate with more side protection. As long as you
understand the trade-off you are making (primarily weight and cooling), you won’t be
unhappy with your decision (especially if you avoid hot summer riding).
Q. What about raising links?
A. The reason I don’t like raising links is that they are a solution to a symptom, not the
problem. The problem is the stock spring (KLR) which is too light for most riders. This is
why you end up with excessive sag and not being at the proper ride height. Raising links
compensate for the crummy (too light) spring by starting off “higher”; you'll still sag too
much, but the end point will be about where you should be with a proper spring. So, if you
only ride on the street and you don’t brake hard, raising links might actually work. But… if
you want to ride off-road, you will have less than nominal travel available, and you will be
starting farther into the rising rate of the suspension – which means a rougher ride.
Additionally, when the suspension unloads you will end up with decreased rake and trail (as
the suspension lightens and tries to return to the starting point) giving you faster steering
right when you might not want it. This same decrease in rake and trail will occur during hard
front braking as well. So, if you can accept less travel, rougher ride, and twitchier steering
when the suspension is unloaded, raising links might be acceptable for you. Or you could
just install the correct spring and solve the problem without all the side-effects.
Q. Can I add a jet kit, modified airbox, and aftermarket pipe to get more power
from my DR 650?
A. Yes, you can, if that’s what you REALLY want. Bear in mind some very smart engineers
have tuned the power delivery system pretty well for general riding, though you can
probably squeeze a few more horsepower out of the motor. But… even if you make the
modifications and dial it in just right, you are STILL increasing the stresses on various
components. Think about the power delivery system. Right from the start, it’s a big
compromise. Power must be compromised with weight. Weight must be balanced with the
suspension and the intended use of the bike. The amount of air flowing into the engine
must be balanced and in harmony with what is flowing through the exhaust. The exhaust
system itself is a compromise between weight, engine performance, noise attenuation, EPA
standards, etc. So when the bike is designed, the entire system is intended to be as light
and as strong as necessary given the stresses intended to be present. Some of you are
probably pretty good at dialing in the engine, but you WILL upset the design balance.
There’s no way around it. Hopefully the engineers designed enough slop into the
tolerances that your changes won’t exceed any critical thresholds. But maybe they will. One
thing I CAN guarantee is that you will lose gas mileage, which costs real money and range.
Two final points. Almost every engine problem we’ve seen on a DR has been on a modified
engine. And... are you really a good enough rider that you can fully take advantage of the
power already resident in the stock engine? I recently read an article in "American
Motorcyclist" about noise ordinances and off-road riding. In a sidebar interview with Jeremy
McGrath, he said that HE couldn’t use all the power in his STOCK motor, and he urged
riders to stop modifying their exhaust systems in search of more “oomph”. Although that he
was specifically talking aftermarket pipes, the point is that if McGrath can’t make use of the
power, we probably won’t either. Need more from your DR? Modify your final gear ratio to
meet your riding needs.