Dirt Bike FAQ

A bike doesn't need to have a 100% Chromo frame and saying it'll break because of this isn't true. When a bike is said to have a 4130 Chromo main frame they are referring to the two main (long) tubes - the top tube & down tube and the seat tube (which is the one the saddle & post are clamped into). You'll normally find the other tubes will be made from high tensile steel and this being the case it should be plenty strong enough as long as the welding is up to the job.

You'll find at this price that the components will be the bits you'll have issues with. Cheaper 3 piece cranks tend to be amongst the first parts to go. You'll often find the splines (the small grooves that hold the crank arm in place on the bottom bracket axle) will strip meaning you'll have to replace them pretty quickly. And no, before anyone pipes up - it won't be covered by warranty if you've been using the bike for jumping / park riding. Even though the bike is designed for this, it'll be excluded from the warranty cover.

Another thing you may need to think about changing pretty quickly would be the wheels. Off the peg wheels tend to be pretty poorly built. Look for something with steel rims (heavier but stronger and better braking), 48 spoke and with a serviceable hub. No point going for cartridge bearings when the wheels are going to take a kicking. And they will. especially if you're learning to jump!

Take a look at the Specialized Fuse Two & Three. Both have good frames and a good level of equipment. The Fuse Three at $400 has a full Chromo frame and slightly lighter wheels. Otherwise have a look for the GT Bump at around $300. All good places to start.

Whatever you get, don't expect it to be unbreakable. Even the really expensive ones get busted, especially if you're just getting started. Remember to save some money for pads & a helmet. And have fun!

While 20" is responsive, 24" wheels roll much better on rough terrain. The rule is the larger the wheel the easier it is to ride over rough stuff especially.

First thing I'd do is a full cleaning, almost taking the bike apart. Its easier to work on something when it's clean. Buy a silencer plug (Pro Grip makes a good one) before washing, keeps water out of the silencer. Before you go out riding, Air pressure (14 lbs) in the tires is good and check the air filter if its dirty (if you see dirt… its dirty). Also Lube the chain w/ a chain lube, NOT WD40 (explanation later) After ride is more important. Clean it again, after washing bike spray the engine, pipe, radiators, plastic, under the fenders, wheels, linkage, swingarm and chain with WD40 (the WD stands for Water Dispersal) then towel off the plastic as best as you can letting the mechanicals dry. After everything is dry, lube the chain (links, not rollers) then spray the engine again w/ WD40 and the plastic and tires and wheels w/ Armorall then wipe it down (it not only makes it look good, but dirt, mud and water come off easier the next time you clean). There should be grease zerks on the KDX so you should probably grease them every other ride or right after you get back from a really muddy/watery ride to blow out any water. Clean air filter every 2 to 3 rides. I would go to your local Kawasaki shop and get a Clymer repair manual for your bike.

http://www.frpoffroad.com/ is probably the best site for KDX products, Jeff Fredette has be racing KDX's for 20+ yrs and should have the parts you would ever want for it.

PS: Never WD40 or Armorall the brakes or seat… you won't like the results

I am sorry to tell you, but, I seriously doubt that you'll will be able to find a dirt bike for less than $500 anywhere. Well, I take that back, you did not specify running, or even with engine, or seat & tank, or wheels. Your best bet would be to do what I did when I was a kid (before dirt bikes were invented, well almost) find an old street bike that still runs strip it down and field beat it,(brings back great memories).

I got my first dirt bike when i was 5 and it was the best day of my life

I think that the L is for larger wheels.

You can confirm that here
http://www.suzukimotorcycles.com.au/modeldetail.php?intBikeID=227

The original Pit Bikes were simply small motorcycles with a 4-stroke, 50cc motor used by adult-sized motocross riders to navigate the pits (an off-track area designated for setting up prior to an event). Pit bikes evolved to look more and more like mini versions of the factory MX motorcycles. Because racers like to race just about anything with a motor, it got to where the “big boys” started racing each other on these pint-sized pit bikes on small impromptu tracks.
Of course, some guys got busy hopping them up with stuff like aluminum frames, tall seats, etc. –– but retaining the over-achieving motors (usually punched out to 110cc), the 10″/12″ rear wheels, and the tossable proportions that make a pit bike such frickin’ fun. Because a track for these bikes doesn’t require a lot of land, backyard pit bike tracks have sprung up all across America.
Pit bikes now have a full race series with numerous classes (even one for young ladies), five AMA National #1 plates up for grabs, and an exciting ArenaCross Pro & Amateur Series.

and then of course the dirt bike is well just your average dirt bike :]

I found this on a previous question which asked the same thing. It was voted best answer.

Dirt bikes are safer for several reasons. Dirt bikes are more like riding regular bikes, which is something that most kids know how to do. The turning of a bike and dirt bike is done less with handlebars and more with a leaning motion. This helps to change the center of gravity, and place the weight of the rider away from the bike when a fall starts. Dirt bikes tend to not fall on the rider during a fall, and if they do, it tends to be less of the bike. In the case of quads and trikes, the rider is almost always confined within an imaginary box located very close to the bike. Falls on quads and trikes tend to be rollover type injuries. Secondly, when it comes to the weights of the two concerned, a similiar size (displacement of engine, or cc) bike will be smaller than a trike or quad. Think about, the parts to control and hold together two wheels would be less than that of three or four wheels. Thirdly, I'll use my own emergency room experience as a doctor. I see far more injuries to children coming from trikes and quads than I ever see from bikes.

Thanks,
Doc Brown