KLX110DMFNN Review: Pros, Cons, and Performance

When Kawasaki introduced the KLX110, it revolutionized the pit bike and youth off-road market. The model code KLX110DMFNN represents a specific variant in the KLX110 lineage—typically associated with a late-model year (often the 2019–2020 generation) that balances accessibility with genuine off-road capability. For parents seeking a durable entry bike for their child, or for adults looking for a surprisingly capable pit bike, this model has garnered a cult following.

But is the KLX110DMFNN worth its price tag in today’s competitive mini-bike market? This article dissects the machine’s real-world performance, highlights its undeniable strengths, exposes its weaknesses, and helps you decide if this little green monster belongs in your garage.

Overview: What is the KLX110DMFNN?

The KLX110DMFNN is a 112cc air-cooled, four-stroke, off-road motorcycle designed primarily for younger riders (aged 10 and up) and smaller-framed adults. Unlike cheaper Chinese pit bikes, the DMFNN variant carries Kawasaki’s legendary build quality. It features a semi-automatic transmission (no clutch lever), electric start (a godsend for kids), and adjustable throttle limiter.

Key specifications for this model include:

• Engine: 112cc, SOHC, 2-valve, air-cooled, 4-stroke

• Bore & Stroke: 53.0 x 50.6mm

• Transmission: 4-speed, semi-automatic (rotary shift pattern)

• Starter: Electric (with kick-start backup)

• Seat Height: 26.8 inches (680 mm)

• Ground Clearance: 7.1 inches

• Fuel Capacity: 1.0 gallon (3.8 liters)

• Tires: 2.50-14 front / 3.00-12 rear

The “DMFNN” suffix in Kawasaki’s naming convention usually designates a specific market region or emission standard (often 50-state compliant in the US). For the end-user, it simply guarantees a bike that starts cold on a winter morning and refuses to break.

Performance: Where the Little Engine Surprises You

The performance of the KLX110DMFNN is not measured in top speed (though it hits ~45 mph), but in tractability and fun factor. The 112cc motor is a torque monster relative to its size.

Low-End Grunt

The bike pulls cleanly from just above idle. Unlike aggressive 2-stroke 65cc motocross bikes, the KLX110’s power delivery is linear and forgiving. A rider can chug up a muddy hill at 5 mph without stalling, or crack the throttle for a small wheelie over a log. For a child learning to judge throttle control, this is invaluable. The semi-auto transmission means no stalling; when you stop, the engine idles, and you simply twist to go again.

The Transmission

The 4-speed rotary transmission is unique. You shift down from Neutral to 1st, then down again to 2nd, 3rd, and 4th. At the top gear, you cannot shift past 4th into a false neutral—it stops. To return to neutral, you shift down repeatedly. This is idiot-proof, but adults note: you cannot “click up” for higher gears. It takes five minutes to learn, and then you forget about it.

Suspension and Handling

The 30mm telescopic fork (front) and swingarm with single shock (rear) are non-adjustable. For a 70-90 lb rider, they work brilliantly, absorbing roots and rocks. For an adult (160 lbs+), the bike sags dramatically. However, the chassis geometry is superb. The 14-inch front and 12-inch rear wheels roll over obstacles better than smaller 10-inch wheel pit bikes. The KLX110DMFNN turns on a dime—you can pivot it around a tree trunk with a flick of the hips.

Top Speed and Gearing

Stock, the KLX110DMFNN tops out at 45-47 mph (GPS verified) on flat pavement. For a 10-year-old, that’s frighteningly fast. For an adult pit bike racer, that’s too slow. Thankfully, a simple countershaft sprocket change (dropping from 14T to 13T front) wakes the bike up for low-speed technical trails, while a 15T front sprocket converts it into a mini-motorcycle for adult cruiser duty.

Pros: Why Riders Love the KLX110DMFNN

1. Unkillable Reliability

The single biggest pro is the engine. The 112cc air-cooled motor is over-engineered. Oil changes are required every 20 hours, but owners have reported going 50+ hours on original oil without failure (not recommended, but a testament to build quality). The valves rarely need adjustment. The electric starter means no kicking in a muddy rut.

2. The Electric Start (and Backup)

Many beginner bikes force kids to learn a kick-start procedure. The KLX110DMFNN comes with a button. When your child stalls on a hill or tips over in a creek, they press a button and ride away. The kick-starter is there for when the battery dies (which takes years if maintained).

3. Adjustable Throttle Limiter

This feature is a parenting lifesaver. A screw on the throttle housing limits how far the throttle tube can turn. You can dial the bike down to a walking pace for a 6-year-old beginner, then slowly open it up as they gain confidence. No tools required after initial setup.

4. Adult-Friendly Ergonomics (for a pit bike)

With a 26.8-inch seat height, a 6-foot adult can comfortably ride the KLX110DMFNN as a pit bike or yard toy. The footpegs are wide, and the handlebar bend is surprisingly comfortable for tall riders. Add a set of bar risers, and it’s a legitimate pit bike racer.

5. Massive Aftermarket Support

This bike shares 90% of its parts with the KLX110 and KLX110L. You want a big-bore kit (143cc, 160cc)? Available. Long-travel suspension? BBR Motorsports makes a full kit. Manual clutch conversion? Bolt-on. The DMFNN is a blank canvas.

Cons: Where the KLX110DMFNN Falls Short

No motorcycle is perfect, and the KLX110DMFNN has some frustrating compromises, especially if you weigh over 120 lbs.

1. Sprockets and Chain Are Garbage (Stock)

This is the universal complaint. The stock chain stretches within 3 hours of hard riding. The stock front sprocket is a soft metal that wears into a hook shape quickly. First modification: Buy a heavy-duty aftermarket chain (RK or DID) and steel sprockets. If you don’t, the chain will slap the swingarm, derail, or snap.

2. Shocks Are Underdamped for Anyone Over 100 lbs

The rear shock is essentially a pogo stick. If you are a 180-lb adult, the bike will bottom out over a speed bump. The front forks dive hard under braking. While the bike moves with an adult aboard, the suspension becomes dangerous at anything above 20 mph off-road. You will either learn to ride like you’re on a pogo stick or spend $600+ on aftermarket suspension.

3. The Seat Is a 2×4

Kawasaki clearly spent zero R&D on seat comfort. The foam is hard, narrow, and shaped like a brick. After 30 minutes of trail riding, your sit-bones will ache. After 2 hours, you’ll be standing. Adult owners often buy aftermarket tall seats with gel foam.

4. No Clutch (for some)

The semi-auto transmission is a pro for beginners, but a con for experienced riders. You cannot pop the clutch to loft the front wheel over a log. You cannot engine brake into a corner as aggressively. If you’re an adult wanting a mini-moto track bike, you’ll need to buy a $200 manual clutch conversion kit.

5. Drum Rear Brake

In an era of disc brakes, the KLX110DMFNN still uses a mechanical drum brake in the rear. It works fine in dry conditions, but in mud or water, it fades and becomes grabby. The front disc brake is excellent, but the rear feels like a bicycle brake from 1985.

Maintenance: What You Must Know

The KLX110DMFNN is low maintenance, but neglect kills any bike.

• Oil Changes: Use 10W-40 (0.8 quarts). Change every 10-15 hours of hard riding. The engine has no oil filter; only a mesh screen. Clean the screen every 3rd oil change.

• Air Filter: The stock foam filter is mediocre. Buy a Twin Air filter and oil it properly. Clean after every dusty ride.

• Valves: Check clearance every 30 hours. Intake: 0.10mm, Exhaust: 0.15mm. They rarely move, but when they tighten, hot starting becomes hard.

• Chain Tension: Check before every ride. That stock chain stretches fast. You want 0.8-1.0 inches of slack at the midpoint of the swingarm.

Performance Upgrades (The Top 3 Mods)

If you buy a KLX110DMFNN, plan on these three modifications immediately:

1. Heavy-Duty Chain & Sprockets ($80): Renthal or JT sprockets (14/14 or 13/14) with a non-O-ring chain. This solves 80% of the bike’s drivetrain failures.

2. BBR Heavy-Duty Springs ($120): If you are over 120 lbs, install BBR’s fork and shock springs. It raises the bike 1 inch and stops bottoming out.

3. ProTaper Handlebar ($70): The stock steel bars bend the first time the bike tips over. A quality aluminum bar saves your knuckles.

Who Is the KLX110DMFNN For?

• Target User: A child aged 8–12, 50–100 lbs, first real off-road bike.

• Secondary User: An adult pit bike racer or RV camper who wants a portable toy and is willing to upgrade suspension.

• Not For: A 200-lb aggressive trail rider who expects motocross performance, or anyone who refuses to perform basic chain maintenance.

KLX110DMFNN vs. The Competition

The KLX110DMFNN beats the Honda CRF110F on suspension travel and adult ergonomics. It beats the Yamaha on electric start reliability. It destroys Chinese bikes on parts availability and safety.

Long-Term Ownership (5-Year Review)

Owners who maintain their KLX110DMFNN report the following after 5 years:

• The electric starter motor still works (replace battery once).

• The stock rear drum brake shoes last 4+ years.

• The plastic faders (frame guards) wear out; replace with aluminum.

• The bike retains 60-70% of its original value.

The only common long-term failure is the ignition coil (cheap fix) and the shift lever bolt loosening (use blue Loctite).

Final Verdict: Should You Buy the KLX110DMFNN?

Score: 8.5/10

The KLX110DMFNN is not the most powerful, the lightest, or the cheapest mini bike. But it is arguably the toughest and most versatile in its class. It offers a level of build quality and performance adjustability that Chinese bikes cannot touch. For a family wanting a bike that can be passed down from an 8-year-old to a 12-year-old and then turned into an adult pit bike, this is the gold standard.

The pros (reliability, e-start, throttle limiter, and aftermarket) massively outweigh the cons (bad stock chain, weak suspension for adults, and drum rear brake). If you are an adult buying this for yourself, factor $300 into the purchase price for chain, sprockets, and heavy-duty springs. If you are buying it for a child, it is perfect out of the box.

Buy the KLX110DMFNN used, maintain it, and sell it in three years for what you paid. That is the definition of a smart motorcycle purchase.

FAQ: KLX110DMFNN

Q1: What year model is the KLX110DMFNN?

A: The “DMFNN” suffix typically corresponds to the 2019 or 2020 model year in North America. Check the VIN (10th digit) for confirmation: K=2019, L=2020, M=2021. However, Kawasaki uses similar codes; always verify with your VIN.

Q2: Is the KLX110DMFNN street legal?

A: No. It comes from the factory without turn signals, mirrors, or a DOT horn. It is an off-road only vehicle. However, in some states (like South Dakota or Montana), you can add a lighting kit and register it as a street-legal “motorcycle,” but it is not recommended due to low top speed.

Q3: How fast does the KLX110DMFNN go?

A: Stock, with a 150-lb rider, approximately 45 mph. With a 70-lb child, approximately 42 mph (wind resistance matters). Changing the rear sprocket to a 13T front can drop top speed to 38 mph but improve climbing.

Q4: Can an adult ride a KLX110DMFNN comfortably?

A: Yes, for short distances (pit bike duty) or racing on kart tracks. For trail riding, an adult over 5’8″ will find the knees cramped. The solution: Bar risers, a tall seat, and an extended shifter tip. Do not expect to ride 50-mile enduros on it.

Q5: How often do you change the oil in a KLX110?

A: Every 10-15 hours of riding. The engine holds only 0.8 quarts, so oil degrades fast. Use a quality 10W-40 motorcycle oil (not car oil, because car oil lacks zinc for the transmission gears).

Q6: Why is my KLX110DMFNN hard to start when hot?

A: This is usually a tight intake valve clearance. As the engine heats, the valves expand, losing compression. Check valve lash (intake 0.10 mm, exhaust 0.15 mm). Also, ensure the idle is set to ~1,400 rpm (screw on the left side of the carb).

Q7: Can I add a manual clutch to the KLX110DMFNN?

A: Yes. Companies like BBR, TB Parts, and Two Brothers Racing sell complete manual clutch conversion kits ($150-$250). They replace the right-side engine cover and add a clutch perch and cable. You will also need to swap the shift drum to a non-rotary pattern for a true clutch feel.

Q8: What is the difference between KLX110 and KLX110L?

A: The KLX110L has taller suspension (27.4-inch seat height), larger wheels (16/14), and a rear disc brake. The standard KLX110DMFNN has a 26.8-inch seat height and a drum rear brake. For tall teenagers or smaller adults, buy the L. For children under 12, buy the standard 110 (DMFNN).

Q9: Does the KLX110DMFNN have a fuel gauge?

A: No. It has a petcock with “On,” “Reserve,” and “Off.” When the bike sputters on “On,” turn to “Reserve” to access the last 0.3 gallons. Then go refuel immediately.

Q10: Is the KLX110DMFNN a good first bike for a 7-year-old?

A: Possibly, but borderline. A 7-year-old needs to be tall enough to touch the ground (minimum 24-inch inseam). The 112cc power is mellow, but the weight (165 lbs wet) is heavy for a 7-year-old to pick up. Use the throttle limiter screw to reduce speed by 70% for the first six months. Alternatively, look at a Kawasaki KX65 (if they are tall) or a PW50 (if they are small).