The Contact Patch
by Todd Vosper
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Before I get to a couple of questions, I’d like to tell you about a recent early morning
ride. I stepped out of the house around 0540 to get in a quick, 30 minute ride. I usually
try to do this a couple of times a week, though normally I’m out the door 20 minutes or
so earlier than on this day.
About a half-mile out, I noticed that the city sprinklers were hard at work watering some
of the town’s grass. The water was running across the concrete in front of me, so I
slowed as I neared and made an uneventful left turn. I noted to myself that I hadn’t seen
these particular sprinklers on before; maybe a result of a new summer watering
schedule or maybe because I was running a little later than normal. I spent the next 25
minutes or so enjoying the breaking SoCal summer day.
As I returned home, I neared the same wet corner as I’d noticed earlier. I slowed a bit
and leaned into the right-hand turn. As I’d only had a half-cup of coffee before leaving,
my mind was already wandering to my impending breakfast and my stomach was
happily encouraging the lack of concentration. I noted that the concrete was still wet,
“mmm, I could really go for a bowl of cereal. Can’t wait to get another cup of coffee.
Almost forgot about that package I’m supposed to…” I was jerked back to reality as my
front wheel lost traction on the wet pavement. Since my head wasn’t in the game, I was
able to recognize, but not react to, the loss of traction. In a metal-scraping thump, I
slammed into the concrete. I quickly jumped up, assessing my situation: I’m OK. I picked
up my ride and looked it over – it appeared none-the-worse-for-wear. Cursing my own
stupidity, I saddled up and pedaled home.
Did I mention I was on my mountain bike?
On the short ride home, my now-focused mind realized there were a lot of parallels
between my “low-side” and riding motorized bikes. Let’s take a look at some of the tell-
tale signs: close to home, complacent, “been there a thousand times”, ignoring my own
mental note about the change in surface from normal conditions, not focusing on riding,
not being ready to react to the worst case scenario. I also had a poor choice of tires for
street riding on wet pavement – essentially a smooth center tire with very aggressive
knobbies on the edges for cornering in dirt. It’s supposed to be a tire that does a little
bit of everything, though nothing particularly well (sounds kind of like a “dual sport”
tire). I basically ended up in the turn with one small piece of wet rubber for a contact
patch. How about gear? Well, I had bike shorts on that came down to my knee. That
saved a substantial amount of skin on my hip and left me with only superficial road-
rash. A few scrapes on the side of my shin were my most serious injury. The heels of
my hands were sore reminders on the way home that I was glad I had padded bike
gloves on. Now for the big confession: I wasn’t wearing a helmet. Why? Because I ride
my bicycle to work most days and I don’t like putting on a sweat-soaked helmet. So I
decided to just wear a hat this morning and save the helmet for my ride to work. Darn
good thing I didn’t knock my noggin; that would have changed the complexion of this
little incident immensely. I won’t make that mistake again.
Lessons learned? 1. Stay in the game. Focus, don’t become complacent. 2. Equip your
bike properly for your riding. 3. Wear protective gear for every ride.
As I sat at my desk checking some email after breakfast, my beautiful bride poked her
head in and noticed my leg. “Oh, are you hurt?” “Naw, not bad.” She gives me a hug,
“Are you OK?” “Yes sweetie.” “Did anyone see you?” “No darling.” “Good!” she says
with relief at knowing she’s narrowly avoided the public embarrassment of a clumsy
husband, and immediately walks out. Ah, it’s nice to be loved…
Q. My DR650’s upper chain roller is missing. Should I replace it?
A. This is not the first time we’ve been asked this question. There are numerous
Internet threads about upper chain rollers breaking away from the DR650 frame. Rod
Morris, Elden Carl, and I have accumulated over 100,000 miles on DR650’s, and I think
I could conservatively estimate that at least 20,000 of those miles have been off-road.
We’ve replaced a number of worn rollers, but have never had one break away from the
I know of one Internet acquaintance who admitted that he broke his roller off while
jumping the DR650. It’s important to select the right tool for the job, and that includes
motorcycles. If you don’t, you’re bound to be disappointed in the results and/or
performance of your bike. If you want something with the raw power of a dirt bike, a
premium suspension for hard off-road riding, jumps, etc., then go get one. We suspect
that a combination of weak welds and excessively hard riding (harder than the bike was
designed for) are the culprits. I also noted a post on the Internet by someone using
17/52 gearing who had broken off his upper roller (and admitted it was because of the
bigger sprockets). If you are using bigger sprockets, you WILL put more pressure on
your roller because the chain will be in contact more often, and for longer periods of
time. One note – 17/52 yields a final drive ratio of 3.06 while 14/43 yields 3.07.
If you DO find yourself airborne on your DR650, do you and your bike a favor and stay
off the gas until the suspension settles out after landing. The absolute worst case for
your upper chain roller is with the suspension fully compressed and throttle rolled on.
As for whether or not to replace the roller, we think that you should. As a result of the
research we did developing the KLR650 Chain Master (add link), we are convinced that
taking out excessive chain slack on the upper chain run will increase the life of your
chain and sprockets. We will continue to look into this problem and are currently
evaluating several solutions.
Q. Do I need a fork brace on the 2008?
A. After all of the major magazine write-ups condemning the 2007 and earlier KLR forks
as “wimpy”, “noodly”, etc., while extolling the virtues of the 3mm larger 2008 forks; we
were very surprised at how fast the aftermarket responded with a fork brace for the
2008. For the record, we’ve never agreed with the aftermarket that the 38mm forks
were inadequate. With proper set-up, the pre-2008 models work just fine.
We’ve talked about this before, so I won’t belabor the point. We believe a fork brace is
only appropriate in certain situations. If you are an aggressive street rider, particularly if
you’ve upgraded your front brakes with a larger disc, better pads, proper stainless steel
brake line, etc., and you brake hard enough to notice the front end twisting under
braking, you might benefit from a fork brace. The downside to the fork brace is adding
some extra weight to the front (it’s small, but everything adds up) and with certain
models, you may damage your fender at full compression. Depending on the fit, design,
and adjustability of the particular model, they may also increase stiction and fork binding
We set up our KLR front ends properly by ensuring the wheel is centered and the forks
are properly aligned (most KLR wheels are not!). We also upgrade the too-skinny front
rim, increase the spoke size, and keep our steering head bearing properly adjusted.
Getting back to the 2008, we would not recommend a fork brace. We upgraded our
2008 to a 2.15” front wheel with the 2008's larger spokes and it feels very well-planted
in turns and on the highway in general.