2007 Kawasaki KFX 50 and 90

Test Rider: Ryan Wheeler

 A few months back we told you about two new youth models from Kawasaki, the KFX50 and its larger sibling, the KFX90. As we mentioned back then, 2007 marks the end of the cooperative agreement between Kawasaki and Suzuki, so team green will no longer be offering rebranded versions of the LT50 and LT80. With this cooperative venture having come to an end, Kawasaki went to work on two new four stroke models to replace the departed 50 and 80 machines of old.

A New Cooperative Agreement
Rather than go to the drawing board and spend millions of dollars developing new machines from scratch, as they did with Suzuki, Kawasaki decided to form another cooperative agreement with a new company that could manufacture their new machines. Over the past ten years, the quality of the machines coming out of Taiwan has greatly increased, especially from the more prevalent brands. Knowing this, Kawasaki worked with Kymco, a brand that you are most likely familiar with, to develop their new KFX machines.

Both the 2007 Kawasaki KFX50 and KFX90 are four strokes and share identical chassis, suspension, and styling taken after their soon to be releases KFX450. Available colors are green and white.With more stringent emissions standards being enforced around the U.S., Kawasaki knew they needed to work with a manufacture familiar with four strokes. Many of the other brands out of Taiwan are still relying on older two strokes; however Kymco had already developed a 90cc machine and was in the process of replacing their old 50cc two stroke machine with an all new four stroke model.

Kawasaki decided that Kymco’s machines were good enough to use as a base design. Later Kawie was so impressed with Kymco’s production quality they actually hired them to construct the new machines. According to Kawasaki, while the machines are similar, there were quite a few small changes made besides color and styling to make sure that the machines lived up to Kawasaki’s standards and expectations.

Both KFX models utilize mechanical drum brakes up front and a hydraulic disc in the rear. Both brakes are actuated by handlebar mounted levers.

Giving everyone a chance to cool off, Kawasaki brought out a pair of their 800cc SX-R stand up Jet Skis. Yes, the stand ups are tricky to ride for first timers, but the thrill of these high performance machines combined with the chance to cool off sent many test editors into the drink.

The 90’s larger tires help smooth things a bit over small bumps and give the larger displacement a bit more ground clearance.

What Makes Them Tick
Both the KFX50 and 90 have air cooled two valve motors, which measure in at 49.5cc and 89cc respectively. Both engines are fed by 16mm carburetors, however the 90 draws its fuel through a Keihin while the 50 sips through a Mikuni. To keep things simple for youngsters learning the ropes, Kawasaki equipped both machines with fully automatic CVT transmissions. Final drive on both machines is handled by chain and sprocket set-up.

In the chassis department both machines are virtually identical. Both feature a conventional tubular steel frame design and are fully suspended. Up front, both machines use preload adjustable shocks mated to a single A-arm design delivering 2.8 inches of travel. Out back the swingarm with preload adjustable shock features 2.9 inches of travel. These suspension numbers won’t set the mini ATV world on fire. To be honest we were a bit disappointed that Kawasaki didn’t step up with a dual A-arm design. Dual arms allow the front wheels to maintain the same camber throughout the suspension stroke. On single A-arm units the wheels leaning farther in as the front wheels go through the travel which results in the wheels scrubbing across the ground as the suspension compresses.

In the brake department, both new minis feature dual manual drum brakes up front and a single hydraulic disc in the rear. Both brakes are independently actuated by levers on the handlebars. As on larger ATVs, the right hand lever operates the fronts and the left takes care of the rear. While there is no foot lever to operate the rear brake, the handlebar mounted levers are appropriately sized for the smaller hands of young riders.

 Both of these machines feature a laundry list of safety features that will comfort mom and dad without hindering juniors fun. Both machines come standard with full floor boards with raised foot pegs; we really like this setup on youth ATVs. Giving parents more control, both machines feature a throttle limiting screw and a collard sleeve inside the driven pulley in the CVT transmission. The collard sleeve won’t allow the clutch to engage completely limiting the top speed of the machine even if the throttle limiting screw isn’t being utilized. This will come in handy if you have a sneaky speed hungry youngster. Once a rider gains experience, dad can easily switch out the collard sleeve in around twenty minutes.

A safety feature that is unique to the KFX50 is the walk behind tether kill switch. Mounted on the rear of the machine, the tether kill switch allows mom or dad to walk or jog behind with the ability to pull the plug and kill the motor should junior get into trouble. One final safety feature that we appreciate as much for security as for safety is the KFX keyed ignition. Not only will this help keep someone from hopping on your kids machine and riding off, it’s a good way to limit the use of the machine during unsupervised times.

Besides the obvious security reasons, we like the fact that parents can prevent the machines from being ridden during unsupervised times. They each have a throttle limiting screw allowing mom and dad to restrict the amount of throttle that is accessible and removable internal speed restrictors in the CVT trannies. For added parental control, the KFX50 features a walk behind tether kill switch so parents can pull the plug if necessary. We feel these machines are pretty safe indeed. Ergonomically, the machines are identical. The relationship between the pegs, seat and handlebars are the same on both machines. Considering that the KFX50 is designed for riders six and older and the KFX90 is designed for riders twelve and up, there are lots of different body sizes that this single design has to accommodate. The only real noticeable difference between the two machines are the wheel and tire setup. The KFX50 uses 16 inch tires mounted to 7 inch steel rims while the KFX90 uses 18 inch tires mounted to 8 inch steel rims. Both machines use high quality Maxxis meats all the way around.

Dimensionally, the machines are very similar with only a few minor differences due to the different tire setups. Overall length on the 50 and 90 measure in at 35.1 and 36.1 inches respectively. The 50’s overall width measured in at 34.7 inches, while the 90 measures in at 35.6 inches. Both machines feature a wheelbase of 38 inches and thanks to its larger Maxxis tires the KFX90 enjoys a bit more ground clearance at 5.9 inches while the 50 is a bit short with 5.3 inches.

Let’s Ride

For Kawasaki’s press intro we took our ace mini tester and highly experienced 90cc production racer “Flyin” Ryan Wheeler with us to Temecula, California. Kawasaki loaded all of us in a short bus and hauled us out to a remote location where they had set up a small motocross course. Besides the test track they had built, the location also features miles of fire roads as well as plenty of boulder piles for Ryan to test his rock-crawling skills and there were twenty brand new fully unrestricted KFX50s and KFX90s to choose from.

The KFX90 has plenty of power for catching some air. Ryan felt that the machine was easy to control in the air, however landing from several feet of air resulted in bottom the machine’s suspension at both ends. While the suspension is fine for the trail, we wish Kawasaki would have used a dual A-arm design with a few more inches of travel at both ends, at least for the 90.

KFX90
The first machine Ryan grabbed was the KFX90. Since the machines share identical chassis, the 90 would give us the best indication of the limits of the machine’s handling and suspension. With electric starting and auto choke, the KFX90 fires right up with the touch of a button and was immediately ready to roll in the 90 degree California sun.

Out on the trail, our fully unrestricted 90 accelerated without hesitation. You get moving pretty quickly on the 90, but there isn’t enough acceleration for big wheelies or throwing roost. The machine carburets well throughout the RPM range all the way to its top speed of around 25mph.

The KFX90s motor and CVT transmission seemed to work together in perfect harmony. The CVT always seemed to keep the motor in the power whether you’ve got it pinned on a fire road or tackling a hill climb. Yes, the KFX90 is a capable climber. You might not be able to keep up with dad on his KFX700, but Ryan managed to climb some decent inclines in spite of there being several inches of loose soil on the surface. The 90 is powerful enough to provide some serious fun with a power delivery smooth enough to keep inexperienced riders out of trouble.

 For a rider just cutting his teeth in ATVing, or for the kid who goes on casual trail rides with mom and dad, the suspension on the KFX90 works fine. Once you start pushing it hard, you soon realize that the machine’s suspension is more at home on the trail than it is on a motocross track. At a casual pace around Kawasaki’s mini test track, the KFX90 handled fine, but once Ryan began pushing the machine to its limit the suspension began bottoming when landing from jumps and packed in the whoops. We didn’t notice the beginner level riders taxing the suspension the way Ryan was, but once your beginner level rider gains experience, you may want to consider some suspension upgrades before you touch the motor.

Through the turns the KFX90 is surprisingly precise. Many youth models have a tendency to push more than we like, but the KFX seemed to go right where you point it. We rode our machine on hard packed, loose surfaces, on banked turns and on off cambers. All the while, we couldn’t fault the machine’s turning. In addition, the smooth four stroke power seemed to work in harmony with the Kawie’s dimensions providing a very stable and predictable ride through the turns.

This hill which Ryan easily concurred on the 90 was more than a match for the 50. The KFX50 is a fun little trail mount as long as the trail doesn’t get too steep.

Both KFX models are excellent through the turns. Steering is precise and both machines do a good job of resisting two wheeling. Pictured right, the KFX90 had enough juice for some radical moves on this off-cambered turn. The machine’s good stability and neutral handling made it easy for our experienced test rider to keep things under control.

Braking power on the KFX90 is decent. While we would like a bit more power out of the machine’s mechanical front drum brakes, the rear hydraulic disc brake was outstanding. Although we like foot brakes on all ATVs, even the smallest test riders could lock up the KFX rear disc brake easily with the handlebar mounted brake lever.

Making the KFX even more appealing is its affordable retail price of $2,149. This will surely have potential Honda TRX90 buyers taking a closer look at the KFX. Both machines are comparable in size and the suspension numbers are extremely close but the KFX costs a cool $500 less than the competition.

For a young beginner to mid level rider the KFX90 is a viable choice. While Kawasaki recommends this machine for riders 12 years and up, in our opinion, an experienced 8 year old should have no problem handling this machine. Still, KFX delivered enough performance to keep our race minded test rider entertained all day long. In spite of the short suspension travel which will hinder the faster 90 pilots, the KFX is still a capable trail machine with very good handling characteristics. The machine seems extremely well built, and in spite of Ryan’s best effort to break it, the machine held up without a whimper. With decent overall performance and what should prove to be a reliable machine, the KFX will make a lot of up and coming ATVers very happy.

KFX50

As with the 90, the KFX50 fires up with little effort thanks to its electric starting with kick start back up. However, we did notice a bit of hesitation to fire from time to time. The first time the rider hits the throttle you notice that the 50 is considerably more mundane than the 90. The machine accelerates to an unrestricted top speed of around 15mph but is in no hurry to get there. Acceleration is fine for beginners, but once a rider gains experience, they will be wishing for more motor performance.
Around camp or on flat trails the KFX50 claws its way around fine, but any decent hill will stop the 50 dead in its tracks. Hills that Ryan tackled with ease on the 90 proved to be too much for its smaller brother.

Comparing the KFX50 to other machines on the market, the KFX is a bit faster than the 2006 Suzuki LT50, but it is also larger than the micro mini Zuk, leaving the KFX out of reach of truly tiny mini riders. If you are starting your six year old out on the KFX expect them to want something more potent by next season, especially if they have a riding buddy with an uncorked two stroke 50.

While several test riders were able to outride the suspension on the KFX90, the identical chassis and suspension proved to be more than a match for the more mellow power output of the KFX50. On the same jumps where Ryan was getting several feet of air on the 90, he was only able to loft the front tires on the 50. Since it is difficult to launch the 50, it’s hard to tax the suspension with any hard landings. Through the whoops or on large bumps on the trail the 50 never seemed to bottom. This was due to the fact that the 50 just isn’t fast enough to push the chassis to the limit.

We like Kawasaki’s full floor boards with raised foot pegs. A young rider has the freedom to pivot his foot while riding without the risk of losing the peg and having his foot run over by the back tire. Bodywork that covers the engine gives the minis a smooth appearance as well.Handling wise, the 50 is perfect for the six year old beginner. With its smaller tires and wheels providing a lower center of gravity and its mellow power output, it would be extremely difficult for a rider to get himself into trouble. Getting stuck on a hillside that is too large for the machine to climb, or winding up sideways on an extremely steep hill are about the only ways a child is going to flip this thing.

Steering is as precise on the 50 as it is on the 90 and as we mentioned with its smaller lower profile tires, it is actually more stable. While it is a good idea for riders to always practice good body position when riding, the KFX50 is so rock steady — a child can virtually sit straight up and hold it wide open through the turns without any tipping.

The brakes on the KFX50 work quite well, even a six year old can lock up the hand operated rear brake with ease. From top speed, the machine hauls to a stop in a matter of a few feet. On the mellow descents that Ryan rode the KFX50 down, the brakes were more than adequate.

For the six year old looking to get into the sport, the KFX50 is a great place to start, but for the parent looking for a machine that will keep their child entertained for three or four seasons, you may find yourself stepping up to the KFX90 sooner than you think. While we do not advocate putting a child on a larger machine than the government recommends, we don’t think that the KFX50 will keep a child with several years of experience entertained for very long. Fortunately the KFX50 should have good resale value when you are ready to step up to the 90 and at $1749 you can afford to lose a few hundred bucks in order to provide your child with a season or two of fun at a comfortable and controlled pace.

SPECS

2007 KFX50
Engine: Air-cooled, four-stroke, single cylinder
Displacement: 89cc
Bore x stroke: 47.0 x 51.8mm
Compression ratio: 10.8:1
Carburetion: Mikuni PTE 16
Ignition: Solid state CDI
Transmission: Continuously Variable Automatic
Final drive: Chain
Frame: Double cradle, steel
Suspension front / wheel travel: Single A-arm with twin shock absorbers / 2.8 in.
Suspension rear / wheel travel: Swingarm with single shock absorber / 2.9 in.
Front tire: AT18x7-8 tubeless
Rear tire: AT18x9-8 tubeless
Front brakes / rear brake: Dual mechanical drums / Hydraulic disc
Overall length: 56.1 in.
Overall width: 35.6 in.
Wheelbase: 38.0 in.
Ground clearance: Center of chassis – 5.9 in.
Track Front/Rear: 26.8 / 26.0 in.
Fuel capacity: 1.5 gal.
Dry weight: 254 lbs.
Color choices: Lime Green, White
MSRP: $2,149

2007 KFX90
Engine: Air-cooled, four-stroke, single cylinder
Displacement: 49.5cc
Bore x stroke: 39.0 x 41.4mm
Compression ratio: 10.0:1
Carburetion: Keihin PTE 16
Ignition: Solid state CDI
Transmission: Continuously Variable Automatic
Final drive: Chain
Frame: Double cradle, steel
Suspension front / wheel travel: Single A-arm with twin shock absorbers / 2.8 in.
Suspension rear / wheel travel: Swingarm with single shock absorber / 2.9 in.
Front tire: AT16x8-7 tubeless
Rear tire: AT16x8-7 tubeless
Front brakes / rear brake: Dual mechanical drums / Hydraulic disc
Overall length: 55.1 in.
Overall width: 34.7 in.
Wheelbase: 38.0 in.
Ground clearance: Center of chassis – 5.3 in.
Track Front/Rear: 27.2 / 27.6 in.
Fuel capacity: 1.5 gal.
Dry weight: 232 lbs.
MSRP: $1,749
Color choices: Lime Green, White

Tags:

Comments

comments