Off-road racers have long fought the battle of trying to find the right machine for enduro-style racing. Each bike manufacturer makes excellent motocross bikes and worthy off-road machines. In the case of Kawasaki, this is the KX450F and KLX450R, but the enduro is aimed at regular trail riding and general-purpose use rather than hard-core racing. We know that Kawasaki’s KX is one of the burliest machines available, but does the KLX have a race-winner buried beneath its trail-friendly exterior? Can you buy this bike and race it the same weekend?
Generally speaking, today’s serious off-road racers are in a trend of converting the hard-hitting, aggressive motocross bikes rather than shedding weight and spicing up enduro machines. We wanted to buck that trend, but didn’t want to spend all of our resources (time/money) to do it. It’s understood that some basic modifications are needed, so we threw a few parts at it and headed off to the Ghostriders MC Phantom Hare Scramble in Hollister, California.
We tested the KLX450 back in 2008 during our 450 Enduro Shootout, and while it performed well, it didn’t strike us as the ideal race bike. We wanted to do the race with as few modifications as possible, but there were a few areas to address if pushing this bike to its limits for two hours.
The stock KLX has a great motor for tight trail riding. The thing is like a tractor, so you can bog it without fear of stalling or over-using the clutch. Out on the open road, the user-friendly motor could use a few more peak horsepower and some added top-end. First gear in particular is extremely low, unusable for anything but the most disgusting terrain. Our tester typically likes to rev his bikes pretty high, and the stock KLX falls off early for his riding style. To help correct this problem we installed a Dubach Racing full system stainless/aluminum exhaust. It not only gave us a little more up top, but also comes with a spark arrestor and met the sound requirements of the event.
Changing the stock 5.0 N/mm shock spring for a heavier 5.4 N/mm was the best modification we made for this project.
The other area we felt the bike might struggle under race conditions was the suspension. The stock springs work for trail riding, but for heavier riders and anybody going fast they are under-sprung. We did some suspension testing the day before the race and swapped the shock 5.0 N/mm spring for a heavier 5.4 N/mm coil. From there we were able to adjust the race sag correctly and get the bike to resist squatting in the rear. More emphasis on the front end helped make the bike turn better, but it still isn’t the quickest machine in tight terrain.
We threw on some Renthal Twinwalls for added durability and a set of green Acerbis Uniko vented handguards to deflect the brush. Our Dunlop MX51 rear tire only had a day of testing on it and was in great shape. Off came the kickstand, on went the temporary number plates and the bike was deemed race-ready. Would our minor modifications be enough? It was time to find out.
Our 37-year-old test pilot entered the Vet B class alongside 22 other riders in Saturday’s morning race, which was the last of seven classes to leave the line. With overcast temps and one-minute intervals between waves, it was about as good as it would get for the dead-engine start.
With a total of 145 riders on the course, a botched start left us in about 144th – nowhere to go but up! At the end of the first lap, the KLX was into 80th, which is a ton of passing on a course that features significant portions of single track. After working through the pack on Lap 1, only two Vet B riders were in front and we were a minute out of the lead. Despite having a slower lap time on the second circuit, we moved into second and cut the gap to just 10 seconds.
With more feel for the front end, the Kawasaki was easier to point where needed and the overall turning ability was quicker. Fortunately, it still retains its stability.
Our race strategy came into play at this point as we opted to pit before heading out for the final loop. We weren’t exactly razor sharp with our pit stop, and after spending 1:02 getting fresh goggles, fuel and a giving a quick update to the crew it was back onto the course for a final lap. Another rider managed to slip by and hold us off for the remaining circuit, landing us on the final podium step – 44 seconds out of second, and 1:11 off the winner. Considering the 18.7-mph average speed, we might have been able to get by without stopping for fuel, but with only 2.1 gallons it would have been pushing our luck. That’s the way racing goes, and third is better than a long walk back to the truck.
Hollister Hills SVRA has two main riding areas – the upper and lower ranches – separated by a few miles of highway. With the upper closed off for the event, our pre-race testing was conducted at the lower ranch. What we didn’t realize was how different the trails were. The lower was wide open with deceivingly slippery hard-pack. Even the single track available was fairly wide and our riding speeds were much higher than what they were during the race. As such, we were in 2nd/3rd/4th gears for testing where the race required primarily 1st/2nd. Like all transmissions, there’s a bigger gap and more opportunity for missed shifts between the first two, and like we mentioned, the KLX’s lowest cog is virtually unusable for anything but the slowest terrain. By the time we realized the situation on the first lap, it was too late. Forced to ride between gears, a simple sprocket change would have made a huge difference. We should have geared it down so that second could be an effective workhorse, using the
The Kawi proved that it can be raced with success at the amateur level, but it’s still a great trail bike without any modification.
engine’s abundant torque to carry third. At least we swapped out the low-boy exhaust header for Dubach’s straighter version. It helped the bike rev and probably saved us any time we dropped into first.
The mild changes made the KLX a better package, but over the course of the two-hour race, we learned that there were some other areas that might have been a better target for our low-level upgrades. Gearing was one, but also the brakes. Hollister is hill country, and while the elevation change isn’t huge in terms of sheer vertical feet, the terrain is steep. A stock KLX450R weighs in at 277 pounds (curb), which is a lot to slow down at race pace, especially on a steep downhill. Something as simple as brake pads could’ve made a difference, but an oversized front rotor setup would be the way to go.
Was our goal accomplished? As a short answer, yes. Would our bike have won at the national level? Almost certainly not, but a podium finish proves this bike is a capable racer for the Everyman Kawasaki rider. Just some simple mods with a miserly budget and it still remained a great trail bike.
Brian Chamberlain – Vet B, #235
My class was the last of seven rows. As always, the start was going to be very important. I lined up on the far right, giving me the inside line into the first turn, then warmed the bike up in preparation of the dead engine start. I did a few test starts, thumbing the electric starter, making sure that the bike fired quickly. We had moved the starter button away from the throttle to accommodate the handguards, which was causing me a bit of concern as I had to take my hand partially off the throttle in order to push the button. I did a few more tests as the rows in front of me took off and the bike fired perfectly every time.
What I didn’t count on was the starter’s shotgun. Perched on the sideline, about 10 feet from my head, this was the signal to start the bikes. The gun went off; I hit the button, grabbed a handful of throttle and dumped the clutch. Nothing happened. Temporarily deafened by the gun blast, I think I grabbed too much throttle before the bike actually fired. A quick second attempt got me started, but I was already last off the line. Now I really had to put the big KLX to the test.
The nearby gunshot didn’t help the start any, and once we were underway we had our work cut out for us against the Vet B class.
Once I finally got underway, I rode a pretty aggressive pace to try and make up time and positions. During this period of really pushing the bike, I could quickly determine how well it was set up for this kind of pace, how much our modifications had improved the stock bike and which areas still needed some tweaking.
Our Dubach exhaust had definitely made a difference. The motor maintained its user-friendly demeanor and tractability, but the DRD gave it a little more character. The motor had a little harder hit as well as some much-needed top-end. The terrain was a good mix of tight single track and some wide-open skid roads. The motor performed fine in both areas – controllable in the tight stuff and still powerful enough when stretching its legs.
What we lacked in gearing, the DRD exhaust header helped make up for with better engine performance and top-end.
One area that we could have improved was gearing. Most of our testing the day before had been done on open trails where the bike was comfortable in second and third gear. The tight stuff on the race course was a little too tight for second gear and my high-revving nature; yet first gear on the KLX is way too short. I was constantly shifting between the two and never found my happy place. This is a simple change that any rider will need to do based on the situation.
As the race progressed and the course continued to deteriorate, suspension setup became increasingly important. The heavier spring we put on the rear was working well. The shock was not only soaking up the big hits better, but it also got the bike to turn a little quicker. I think I could have spent a little more time dialing in the front as it was still too soft and wasn’t soaking up the braking chatter as well as I would have liked. A few more hours of playing with the compression and rebound could have resolved most of this, but to get the forks really dialed in they needed different springs and valving – which was outside of our parameters for keeping things simple.
Under race conditions you quickly find things that need improving that were not apparent under normal conditions. This
Kawasaki KLX450R Parts List
DRD Stainless/Aluminum Exhaust – $620
Dunlop MX51 Rear Tire – $104
Acerbis Uniko Vented Handguards – $39
Acerbis Uniko Plastic Mount Kit – $12
Renthal Twinwall Handlebars – $120
Renthal Kevlar Grips – $20
was the case of the brakes. Under normal riding the front brake worked great and provided plenty of stopping power and good feel at the lever. Our race course had some pretty long and steep downhills, and getting the big KLX slowed down was a bit of a chore. Some aftermarket lines and pads would probably improve things quite a bit. An over-sized rotor would be even better.
As the two-hour race drew to a close, I was surprised at how much energy I still had in the tank. Although the KLX is a little on the heavy side, the docile motor makes managing power delivery a breeze – totally different from the Honda 450 motocross bike I usually ride. You’re never fighting with an arm-ripping beast; you’re just putting power to the ground and doing it smoothly. The bike ran perfectly the entire race with no mechanical problems or hiccups. I did manage to stall the motor a couple of time as I was sliding down some steep hills, but a quick hit of the button quickly fired it back to life.
At the end of the race I was content with my third-place finish, and happy with how well the relatively stock KLX performed. A few additional minor modifications or even just some better suspension adjustment on our part could have probably turned my third place into a win. Of course, if I had just gotten a decent start… I guess there’s always next race.