2003 Kawasaki KLX300 Review – Rival of The Honda XR


It’s always been known that Honda XR’s are pretty much bomb-proof trail bikes. It would seriously take some long and hard abuse to kill one of those things. But in this day and age, the XR is becoming more of an out-dated piece of machinery compared to the modern high-tech dirt bikes. Kawasaki has been making the liquid-cooled KLX300R trail bike since 1997, but in 2003 it got a nice face-lift. The KLX300 is in the same class as Honda’s XR250R, but even with the extra displacement, it will still be hard to beat the mighty, air-cooled XR.

More power is better, but it won’t do you much without having good handling, suspension, ergonomics, and reliability, as well as light-weight. Combining the five would give you the best trail bike possible; extra horsepower is a bonus in my book. But since riders aren’t all the same size, shape, and skill, it’s hard to make the best overall bike possible. Kawasaki succeeded in some areas, yet didn’t quite meet the standards in others when building the KLX300.

2003 Kawasaki KLX300R

One of the first things I noticed about this bike is that it has mx-style inverted forks, unlike its XR competitor. This makes it feel and ride more like a motocross bike, but with really plush springs.

Handling is surprisingly good on the KLX300. It’s easy to turn and will go where you want it to. It does get a little twitchy going fast over rough ground, but it handled every terrain I rode on excellently. The bike doesn’t feel too bulky, and the seat is low and comfortable; perfect for my short frame and legs. It’s easy to squeeze your legs right up against the frame and let the bike do most of the work. Although, hanging on with your arms is awkward at first. I’m not really sure what Kawasaki was trying to do when they made the handlebars. They are really wide, low, and weak. Unless you’re an odd-ball that likes the fit of the bars, they would be the first thing to go.

Although the KLX300R has motocross-style suspension, it does not perform exactly like it. It’s a smaller and cheaper version of it. You can’t tune the forks and shock as you would be able to on a race bike. With that said, many KLX owners have swapped out the stock forks for a pair from an older KX250 (there may be a future article on how to do this if I get enough responses). With some adjusting of what clickers I had, the bike was finally riding like it should. I’m a light rider, and I had to have the clickers almost all the way in for it to be stiff enough. I do occasionally jump the bike, but its main use was riding single track trails, so the suspension couldn’t be too harsh. If you weigh over 150 lbs (68 kg) you’ll probably need to get stiffer springs, and it will be well worth it once the bike is set-up the way you want.

Weighing in at 231 lbs makes it the lightest bike in its class. This is a huge bonus because you definitely feel the extra weight on heavier bikes when shifting around on the trails, or when you are picking the bike up after a spill. It’s not as light as a 2-stroke, but definitely lighter than a 450cc off-road dirt bike.

As far as reliability goes, the KLX300 is as close to bullet-proof as you can get. There were a couple problems in the engine, but the main one was the cam/timing chain tensioner. After a few thousand miles or so of wear it would get caulked down, causing the chain to be loose and make noise. Many new KLX owners get frightened by this because it often makes a loud knocking noise. The same thing happened to my 300R, and I thought for sure it was piston-slap since the noise was really loud and would go away once the bike was hot. I eventually bought a new tensioner just for the sake of it, and when I was taking out the original one, it didn’t even look crooked or broken. I was hoping that it would still somehow be the problem, and I was right. I started up the bike with the new one in and it purred like a kitten.

Other that, I haven’t a problem with this bike. As long as you change the oil/filter, clean the air filter, lube chain, etc. when you should, this bike will last a long time. Check the valves and timing chain every year or two, as well to make sure they aren’t worn or have moved.

2003 Kawasaki KLX300R

Lastly, when I said power was just a bonus on a trail bike, I didn’t exactly mean that power doesn’t matter, because it does…. From some help of the extra 50cc’s, the KLX300 is the most powerful in its class. More horsepower and torque than the XR250R and DR250. Don’t get too excited, though, because the 24 ponies it puts out makes a very smooth and linear power curve. This is mainly thanks to the Keihin CVK 34mm constant velocity carburetor. It uses the pull of vacuum to move the slide up, which takes away any “snap” the bike would have had. It simply robs torque and horsepower that this bike could’ve had.

On the flip-side, having a very mellow power-band makes the bike extremely easy to use and allows it to putt up steep hills with ease. You shouldn’t have trouble going through tight trails, no matter the conditions, because it will put what power it has to the ground with a good rear tire on.

All-in-all, there are ups and downs to the Kawasaki KLX300R, but most of the flaws are easily fixable. I wouldn’t mind getting another one of these in the future for going on long trail rides. So, let’s review what this bike has to offer…

What’s good?

  • Lightest four-stroke in its class
  • Very easy to ride
  • Motocross-style features (inverted forks, liquid-cooling)
  • Smooth power-curve to putt up hills
  • Sips on gas
  • Reliable
  • 36 in. seat height
  • Very quiet for riding in people-dense areas

What’s not?

  • No electric-start
  • No hot-start (often floods if you stall, making it harder to start)
  • Low, wide, and weak handle bars
  • Inverted forks are not fully-adjustable
  • Throttle requires you to turn it too far
  • Engine is choked up with the small carb. and exhaust

Haul your KLX300 with an Aluminum Motorcycle Carrier.

If you have any questions or concerns, feel free to comment!

P.S. Stay tuned for a future article or two on how to hop-up your KLX300 for cheap!…

-Tom Stark

6 thoughts on “2003 Kawasaki KLX300 Review – Rival of The Honda XR”

  1. when did u get this bike? how much did u pay? where do u get all the money to pay for bikes and to pay for racin and rebuilds?

  2. I have a 1998 klx300r. Nice bike all around. First I yanked the spark arrestor, nice power increase. Then removed the sirbox lid and added a prefilter, huge power difference, then I swapped the stock 34mm CVT to a 34mm DG and it came alive. 4th gear wheelies with no effort around 40mph and a slight clutch lever twitch and she is airborn. I can and will say that these few little changes make this great little bike run with a slightly modded DRZ400 until 75, then pass it. It will beat a honda ATC250r all day long, 125 2-strokes haven’t a prayer, and the 250 2-strokes better get on that throttle cause they have hardly a chance to beat this little bike. I have video of my little klx dragging all these machines ALOT and beating them…ALOT.

    1. Yeah, they are pretty choked down from the factory. Getting more power out of these is pretty cheap and easy, but you may want to upgrade the suspension since you’ll be riding faster and putting more stress on the bike.

  3. Just picked up a 1998 klx 250e {20.000 miles}
    has anyone changed a cam chain tensioner and what is involved
    my mate said this is a common fault?
    should i bother if i have no excessive noise?
    MANY THANKS

    1. Yes, I changed one on mine. It’s really simple. If I remember correctly, you just have to take out the two bolts that hold it on and swap it out. There should be an o-ring with it as well. If you can barely hear it, I wouldn’t worry about it.

  4. i love my 03 klx 300 just got it last night and have nothing bad to say about,its my daily driver to work only thing i wanna do is put the super moto set up on it

Leave a Reply

Your email address will not be published. Required fields are marked *