Kawasaki KLX140 | Review

Dirt Bike Review

New kids off-road bikes are always cause for celebration, and the Kawasaki KLX140 is one of the newest youth dirt bikes available on the market, geared up to satisfy kids wanting to be the next Chad Reed or Ryan Villopoto, though not ready for the racetrack.

Powered by a slightly oversquare 144cc motor with electric start (hallelujah!), the KLX gets by with a single overhead cam and two valves, but it makes up for it with a redline of 10,500 rpm.

It might sound like it wouldn’t have much low-rpm torque, but the spread of power is as wide as it needs to be. You simply cannot fall off the cam, but there is also no hard hit off the bottom.

The Keihin PB20 carburetor is more sophisticated than you might expect. It has features like partitions in the float chamber to keep the fuel from sloshing excessively, while an umbrella around the main jet traps fuel when jumping.

During our bike-appopriate jumping tests, the KLX140 never bogged. Dual air vents help provide a stable fuel supply and eliminate hesitation even when the bike is at extreme lean angles, and we definitely did some near bar dragging in the turns.

A close-ratio five-speed with manual clutch is perfectly mated to the motor, as there’s always a proper gear for the situation. Shifting is slick and sure.

The clutch pull is light and the engagement comfortingly progressive. This is a superb learn motor/clutch/transmission combination for a new rider or a young rider moving up from auto-clutch bikes.

This is the smaller of the two KLX140s (the other is the larger “L” version), so it gets by with a 17-inch front and 14-inch rear tires. The stock IRC tires work great, but racing tires are also available for those who want an upgrade when the IRCs wear out. Discs front-and-rear handle the braking chores perfectly. This is a far cry from the days of ancient drums.

The KLX140’s suspension is modern, thanks to over seven inches of well-damped and properly sprung travel at both ends. Kawasaki’s Uni-Trak linkage system makes the most out of the rear travel, and the swingarm is aluminum.

Our young test riders took on the type of jumps you find off-road and never complain, and rubber-mounted bars help cushion the landings. Likewise, the suspension is supple on trails, so the balance between performance and comfort for this type of bike (non-racer, non-MXer) is met perfectly.

Ergonomics are also up to date. The steel perimeter-frame is reminiscent of the larger KLX450R, as well as the KX motocross bikes. The seat is narrow with plenty of room for the rider to get up on the tank in corners. However, with the forgiving handling of the KLX140, gymnastics are not a prerequisite for riding the bike. This is a bike that simply couldn’t be easier to handle for a new rider, yet satisfying to a young rider moving up.

Adults can also have fun on the bike. While the L version is better suited to full-size adults, the ergonomics of the standard KLX are not so restrictive as to preclude dad (or mom) from taking it out for a fun spin. Harder charging dads may find the suspension be limiting, but they should just hop back on their KLX450Rs instead of complaining.

Using test rider Wesley Couture to try to pound the bike into submission, we found that the KLX140 was equal to a young man’s best efforts. He put it to the test on a private motocross track in Malibu (no doubles or triples, of course) as well as long trail-riding expeditions with his KLX300-mounted father.

The result was predictable; the KLX was up to the task and had no failures. Maintenance requirements are minimal, and easily accomplished. It’s a good way to teach kids a little bit about taking care of a motorcycle.

Older riders can easily reminisce about the “good old days,” but when you compare this bike to what dad grew up to, the only thing that happens is that dad turns bright green with envy.

Wesley Couture’s words:

The Kawasaki KLX140 is a very nice bike that’s easy to control. The disc brakes really helped me out a lot when I was going down hills. The electric start is a lot better than a tiring kickstarter, especially if you’re stuck on a steep hill.

I had a really easy time getting up and going down steep hills, thanks to the bikes great center of balance and the torque. Geared high and super-fast, this bike is great desert rides, steep sandy hills, and enduro riding.

I crashed the KLX140 a couple of times, looped it, dropped it, and ghost rode it, and it still ran great. It has spectacular suspension, plus a great seat, which is just one of those small things that makes a big difference in a long ride.

I’m about five-feet tall, and weigh 76 pounds, and this bike fits me very nicely. I can touch my feet almost flat on the ground. The KLX140 is shaped great, so if you need to, you can put your foot down easily when going up hills.

When it falls down though, if you are about 11 or 12, you’re going to have some trouble picking it up, unless it is on a racetrack or just a little hill. I recommend this Kawasaki to experienced 11-to-14 year olds who like to do trail rides with their riding buddies.

Motorcycle Specifications

EngineFour-stroke, SOHC, two-valve single


Bore x Stroke58.0 x 54.4mm

Cooling SystemAir

CarburetionKeihin PB20

Compression ratio9.5:1


TransmissionFive-speed with wet multi-disc manual clutch

Final driveChain

Frame TypeHigh-Tensile steel, box-section perimeter

Rake/Trail27 degrees / 3.3 in.

Front suspension / wheel travel33mm telescopic fork / 7.1 in.

Rear suspension / wheel travelUNI-TRAK® linkage system and single shock with

5-way preload adjustability / 7.1 in.

Front Tire Size70/100-17

Rear Tire Size90/100-14

Front brakes / rear brakesSingle 220mm petal disc with a dual-piston

caliper / Single 186mm petal disc with single-piston caliper

Overall length71.7 in.

Overall width31.1 in.

Overall height41.3 in.

Wheelbase49.6 in.

Ground clearance9.3 in.

Seat height30.7 in.

Curb weight205.0 lbs.

Fuel capacity1.5 gal.

Color ChoicesLime Green

Warranty6 months base warranty



Helmet: HJC CS-MX Blizzard

Goggles: Smith Optics

Jersey and pants: O’Neal Mayhem

Gloves: O’Neal Element

Boots: Alpinestars Tech 6