Faults:

The voltage regulator and alternator often overheat and fail, causing the battery to self-discharge or stop charging while driving.

Due to high engine temperatures, individual ignition coils can fail. If you experience jerking or the motorcycle hesitates when accelerating, it's usually a faulty coil.

Fuel pump loses pressure and the motorcycle suddenly loses power at high revolutions or after being stopped.

The hydraulic chain tensioner loses effectiveness with increasing mileage.

Being a heavy and very fast motorcycle, the front brake discs tend to warp if they suffer from extreme overheating (even more so in places where it is very hot for a good part of the year).

General Comments:

I'll start by talking about the engine: a 1200cc, 176hp unit with fuel injection and liquid cooling. The big Ninja's six-speed gearbox is housed in a unique monocoque chassis. It features 43mm inverted forks and a Uni-Trak monoshock, all fully adjustable. The braking system consists of two 320mm discs with six-piston Tokico calipers (which switched to radial-mount calipers in 2004) at the front, and a single 230mm disc with a two-piston caliper at the rear.

The 210kg (dry weight) package is covered by a full sport fairing with a distinctive forced air intake (which further boosts power at high speed) beneath the twin headlights. A big Ninja isn't a small, restricted bike like a liter-class superbike. It's a versatile, full-size motorcycle, a capable sport-tourer with explosive potential.

The extra space makes larger men feel right at home. Furthermore, thanks to the dimensions of the fairing and windscreen, they offer better protection from the elements than sport bikes.

In addition to good overall ergonomics and a comfortable seat, the 12's user-friendly controls make you feel at ease at the handlebars. The cable-operated clutch is light, and the gear changes are smooth and precise. The brakes are powerful and progressive. The throttle response on the first model can be somewhat abrupt when starting and at low speeds.

Despite its focus on high performance, the ZX-12R handles surprisingly well in suburban traffic and at controlled highway speeds.

The rigid chassis and firm suspension provide excellent handling. The larger Ninja is more agile than expected on hilly terrain. Ultra-stable in fast, sweeping corners, it also changes direction with ease on tight sections. This is perhaps due to its aggressive steering geometry, which compensates for its size. Mid-corner at high speed, its front end offers the characteristic Kawasaki confidence. To harness all that torque and launch out of a corner, the rider must rely on a well-trained right wrist to control traction.

Aggressive riding will also quickly wear down the rear tires and drive chain, not to mention fuel. However, at legal highway speeds, you can expect a safe range of around 260 km from the 20-liter tank.

A Kawasaki ZX-12R is not for the inexperienced. But it is an impressive bike.

Faults:

Fork seals blew immediately.

Suspension only adequate for a 150 lb person.

Other than that, call Traxxion Dynamics and tell them your weight, passenger and all accessories weight, and they will build your front springs to spec and will rework your rear.

General Comments:

Nothing performs like this bike. I can ride it like it was a moped. Slow and do 25 or womp on it. Nothing on the highway can touch it. Nothing. She's ultra quick, light and shifts like a Swiss watch. This is a marvelous machine as far as the running gear is. Suspension is not adequate; needs to be tweaked and upgraded to be adequate. She gets 33 MPG.

Now comfort - I call this my torture rack. I'm 5'5. It's horrible on my lower back, shoulders and wrists. My thumb and index finger on my right hand went numb a month ago. It's numb and I can feel it radiating from my shoulder. Additionally, this bike has a horrible vibration at highway cruising speeds. It makes my feet numb. It's not so bad on the knees, and I've had bilateral knee surgery.

My previous bike, the ZX11D and this are nothing alike. I could do 10 hour days on the ZX11. It was way heavier and no vibrations or buzzing; no pressure on my knees, wrists or shoulders. The ZX11 only had one speed. 0-100 immediately. It couldn't be driven conservatively. The 12 kills me after the first 20 miles. A 45 mile ride to work and I want to get off it and never get back on. I'm having a Spiegler handlebar conversion done and hope it gets better.

With all that said, I wouldn't sell it, the drivetrain is so flawless and unlimited that it's worth the back pain. I just had to replace it as my daily driver. I do a 100 mile round trip daily and this bike had me ready to quit my job. I replaced the commute with a $800 82 Honda GL500. I hope my hand numbness goes away; it's been a week off the ZX and still no relief.