Keeping a modern dirt bike in absolutely perfect mechanical condition can be a pretty daunting task. While most of us love the riding part of dirt bikes, only a lucky smaller percentage enjoys working on the bike, too. But even if you get a massive grin at the idea of wrenching, chances are your bike can still benefit from the 10 points covered here. Whether our personal bike, a test bike or even the odd privateer race bike, they all need care that often gets ignored until problems become obvious. None of these 10 steps will break the bank, especially if you do the work, and taking care of these potential problem areas will all but guarantee a fun and trouble-free ride. So hit the garage!

Tech How-To
Just as you wouldn't go wring out the motor before break-in, you shouldn't ride a new bike without prepping it. If you do, you may not pay the price after the first few rides, but the tab will come due. When the bike is showroom clean the basic prep and setup takes less than half the time it would if the bike were dirty. So bite the bullet and get it done.

Tech How-To
A good portion of modern four-stroke engine performance is due to the Keihin FCR carburetor. An accelerator pump and a high-tech slide supported by four wheels make the FCR a relatively complex design. There are many parts that can wear out and get dirty or gummed up. There are a few shops that specialize in mods and service for these carburetors. Some, such as JDJetting (www.jdjetting.com; 253.939.7114) and Factory Pro (www.factorypro.com; 800.869.0497), sell kits that you install yourself, and others, such as Zip-Ty Racing (www.ziptyracing.com; 760.244.7028) and Tokyomods (www.tokyomods.com; 888.457.9403), will set up the carburetor for you or actually modify it for increased performance and response. White Brothers offers both options.

Modern dirt bikes have big, beefy forks with comparatively massive inner steel tubes to handle the rigors of current track and trail obstacles. The combination of inverted design and 47-50mm inner tubes solve any flex problems, but they bring their own headaches. For one, when you get big tubes, there is the problem of seal drag, so manufacturers are always treading a fine line between seal life and seal drag. For another, with the inverted design, the seal is trying to hold in oil sitting above it, rather than under it. Making this more difficult, the backs of the steel inner tubes are exposed to debris thrown by the front tire and the lips inside the seal that actually hold back the oil are delicate and easily cut by nicks in the tubes.

There are times when it is great to be a big guy. Like when you get a toe down and save a big high-side down a hill-one of those deals where you would have plummeted if you were 1 inch shorter. But then there are theater and airplane seats, compact cars and most modern dirt bikes. Manufacturers build for an "average" guy, and that doesn't suit big guys any more than it does short folks. I get a lot of mail asking what I do to make bikes fit my grande chassis, and now that Derek Steahly is on board, he'll be receiving the same sort of inquiries. At just over 6 feet 1 inch and 210 pounds, I am right on the edge with a lot of bikes. I can make adjustments and ride them stock. Steahly is roughly the same size as me, but he is faster, so he generally needs stiffer springs. But this story is more for riders who are completely outside the design window of a stock bike.

The most important step to washing your dirty duds is transporting it properly and cleaning it as soon as possible. Johnson suggests using a mesh-style laundry bag (Shift sells one called the Dirt Bag, www.shift.com) to transport your filthy garments from the track to the washing machine. "After you're done riding, you have a lot of moisture in your gear from sweating," Johnson said. "You don't want all that sitting in a sealed gear bag because the moisture can and will create mold, and mold is what will start to eat away the materials in your race wear. Also, dirt is dirt and it's not clean regardless of where it comes from. The longer that stuff stays on your gear, the more harmful it's going to be for the materials. If your gear is super-muddy, don't just throw it in the washing machine. A quick hose-down or a low-pressure power washing will sluice off the big crud and get your gear ready to wash.

As the sport of motocross has evolved and elevated so has the products built to protect the talented athletes that lead the sport. One of the most popular forms of bodily protection on the line of a pro national is the knee brace. Custom knee braces are necessary for many reasons besides safety. Comfort, unique physical characteristics and personal preference are factors that have more and more riders going custom. But how does one customize a knee brace? Well, if you're Innovation Sports in Southern California you literally build each one of your CTi2 knee braces from scratch. They were nice enough to show us how they do it.

If you ran out and bought a pair of Alpinestars' finest the second they hit shelves last year, odds are you'll need to be replacing those soles any time now. So you head to the local shop and pick up the sole replacement kit. The five-step instructions on the back make it sound easy and simple to change them out, but on our first go at it, we found out it was a more tedious project than we had expected. Here's a quick step-by-step how-to on performing this necessary Tech 10 maintenance.

It wasn't long ago that buying a used bike was very dicey. For one, so many improvements came each year that a year-old bike was technically obsolete; even worse was the bike would most likely be worn out because of the quality of production and materials. But since the mid-1990s, suspension development has settled on around 12 inches of travel, engines all have become water-cooled and disc brakes are standard equipment. More important, though, the quality of production, fit and finish, durability and overall reliability of off-road motorcycles have come to a level at which buying a used machine can be a competitive and cost-effective way to obtain a well-performing bike.

Yamaha's YZ250F has existed for more years than any of the other 250cc four-strokes, so it is less of a mystery—one reason we left it for last in our series on small-bore four-strokes. The other reason is the Yamaha has fewer weaknesses to pinpoint. In fact, we had FMF Racing's Dave Dye show us the intricacies of the engine, and he felt it really had no Achilles' heel. Most recently Dye wrenched for Chad Reed for both the Yamaha factory team and during his stint with Yamaha of Troy, but before that he wrenched for Steve Lamson, Tim Ferry and Brian Swink. However, a race team such as YoT routinely changes valves, pistons and cam chains, so they may never see problems that an average owner—who leaves those same parts in play much longer—might encounter.

A new bike is exciting, but before you fill up the tank and get it dirty, you need to spend some quality time with your steed. No matter if it just rolled off the showroom floor or out of someone's garage, your course of action will be amazingly similar. You need to go over the bike and make some basic adjustments to dial in the machine to match your weight and riding level and the terrain you will likely encounter.

Whenever we're strolling through the pits at a supercross or a National-caliber event that draws the factory teams, we can only imagine what it's like to have some of the trick parts we see on factory machines. Fortunately, as the number of aftermarket companies continues to grow, so does the availability of pro-level componentry with which we can outfit our bikes, so some of the machinery we see at the beginning of the year on our heroes' race bikes are available to the public by year-end. Of course, we will never be able to get our hands on all of the components we see on factory race bikes, but you can get some of the super-trick stuff. What you run depends on how brave you are feeling with your wallet. Some of the items that made Dirt Rider's list are a bit pricey, but on the other hand, a few are relatively inexpensive and a great bang for your buck. In no particular order, here are 15 of the hottest, coolest, slickest parts you can buy.

There aren't many dirt riders who would dispute the fact that technology has been very good to them. We can buy motocross and off-road machines right off the showroom floor that are capable of virtual "Formula 1" performance. This translates into your being able to buy a CRF250R and race supercross or National motocross. Or you could take delivery of a CRF250X and race national enduros or GNCC races. But all technology comes with a price. Frankly, it is amazing that the manufacturers have gotten four-strokes to produce the power they currently do with astounding reliability. Imagine the care your truck's engine would require at 770 horsepower! But these new four-strokes are turning some dumfounding rpm numbers. The 250cc models are in the neighborhood of 13,000 rpm! That means the piston goes up and down more than 200 times a second! Not many engines can live at those rates, let alone live without care and maintenance.

Dirt bikes have come a long way in the past 25 years. It was once common practice to buy a new bike then spend 10 to 20 hours in the garage prepping it before you ever rode your shiny, new mount. You had to go about changing darn near everything before you could take your first ride, much less enter your first race.

Today's bikes aren't cheap, so getting your money's worth out of your bike is critical to your enjoyment of the sport. It's possible to offset the cost of riding and greatly extend the life of your bike if you keep up the necessary routine maintenance. There are many little chores that are easily neglected; such things as lubing the cables after you wash your bike or tightening the spokes properly can allow your bike to not only last longer but to operate better. Some of these tech tips may seem simple, but we feel these seven areas are often overlooked—and have the most potential to save you money in the long run. So we caught up with Pro Circuit's ace wrench Dave Chase and asked him about routine maintenance.

Chains are vital links to the enjoyment of dirt riding. Although the method of transferring power from the engine to the rear wheel hasn't changed much in the last 50 or so years since motorcycle riders began taking their bikes into the dirt, the implements themselves have vastly improved, thanks to better technology and materials.

One of my favorite sayings is "the devil is in the details." In the case of off-road motorcycling, the "details" are the little setup tips and preparation ideas that will help you more fully enjoy the sport and avoid some of the problems riders have encountered over the years. In the jillions of trail miles under my wheels, I have tried to remember and catalog some of the more valuable details that crossed my path. Some I have learned the hard way, and some from other riders. Regardless, the information is no less valuable whether you learned it first-hand or not, although learning first-hand usually seems to be a little bit quicker.

HOW-TO guide INSTALLING GRAPHICS AND SEAT COVERS

With all the hype about Supermoto these days, you gotta know that the best race shops are experimenting with their bikes.

You at home may immensely benefit from our humongous 2003 YZ450F exhaust analysis but it must be duly noted: Knuckles bled, bolts stripped, tires wore, dynos worked and two test riders were beat into submission during our evaluation. To bestow concrete and all-encompassing information upon our readers, the crew went to great lengths to collect data. Each exhaust in our test was first inspected, weighed and measured on K&N's dyno and then caned at Lake Elsinore's motocross facility. Even though several units came equipped with spark arrestors, we removed them to even out the field because this was predominantly a motocross-only test. Spark arrestor or not, if you live in California, you'll be restricted to a motocross track anyway because all of these silencers exceed the 96-decibel sound limit. Since motocrossers are never created equal, we gathered two diverse test riders, Jason "High Rev" Webb and Jim "Low-End Torque" Carley, to suss out which systems worked best for a particular riding style. As expected, the two did not always agree and often held opposing opinions.

The two-stroke engine is quite an amazing creature in itself. This internal-combustion engine is technologically archaic with its oil-fuel lubrication system, reed intake and open exhaust port. But when it comes to building performance through the exhaust system, even Einstein would have pulled out his hair crunching the numbers to milk horsepower, torque and a usable power delivery from a piece of stamped, welded and hammered-on sheet metal. Just a few millimeters off one way or another, and a two-stroke exhaust is nothing but a pile of scrap metal.

Although we appreciate and benefit from the wealth of technology and abundance of testing that goes into each model a manufacturer releases, there are times when the factories screw up, to put it bluntly. On those rare occasions, it's when the bikes are out on tracks and trails across the country that these oversights become apparent. Sometimes, they're simple defects, such as a cable routed incorrectly, demanding excess effort when pulling in the clutch. Other times, they may result in more serious consequences, things that might trigger a "service bulletin" or, in extreme cases, a recall. Companies like PC Racing have homed in on a specific area where manufacturers seem to have dropped the ball--the airbox. Many people don't give their bike's airbox a second thought. They figure it's enough to clean and oil the filter and maybe wipe up around the inside of the airbox once in a while. Sorry, Charlie--not good enough.