Buying A Used Dirt Bike - Dirt Rider Magazine

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.Yet people in general, and men in particular, tend to judge things by how they look (duh), assuming that if a bike looks good, it must be a good ride. Consequently, the motorcycle business has become very skilled at prettying up used machinery. A new fender, a fancy graphics kit, PJ-1/VHT touch-up paint and some silicone polish can make almost any bike appear well-kept. Off-road motorcycles are unique products for how much abuse they must endure, especially considering how often they are washed. As a result of hitting deep mud holes and being hit by 2000-psi pressure washers, bearings dry out and parts rust. The real test of a used bike is not how shiny it is but how well it has been maintained and what kind of mechanical shape it's in. The purchase price is only a part of the cost of restoring a used bike to operating condition. It is not unheard of for unsuspecting buyers to spend more on parts and repairs than on the machine. How can you tell if a bike really is in good shape, not just good-looking? Following are 10 clues to help you avoid buying a lemon in disguise.1. Overall ConditionWhen you go to look at a bike, first pay careful attention to everything besides the bike. Is the garage clean and organized? In what condition is the owner's truck? Does the owner take pride in his stuff? These insights will give you an idea of how your potential new mount has been used and maintained, and they are much more important factors than new graphics. Look toward that inner beauty. Items to note are mangled radiators, smashed frame loops and a rear subframe that doesn't line up with the rear wheel. A radiator costs big, so make sure it isn't on the verge of leaking from stress bends. These are signs of major abuse and frequent crashes. Do a quick check of the condition of the tires and wheels. A set of tires, rims or replacement spokes can be expensive. Also note wear on the frame paint and on the footpeg teeth and pivots, to determine how much the bike has really been ridden.2. Wheel BearingsEven sealed bearings wear out. Under ideal clean and dry conditions, it can take millions of revolutions, but for dirt-bike wheels, clean and dry don't apply. Put the machine on a stand so both wheels are off the ground. Rotate them and listen for any squeaks or grinding noises. Test for any side-to-side movement of the wheel relative to the swingarm or fork. Grab the wheel directly above the axle and, while supporting the bike with one hand, forcefully push the wheel to the left and right to feel any freeplay. There should be zero freeplay, and any movement means that wheel needs new bearings. Expect to pay between $15 and $30, not including labor, to replace bearings. Don't even bother replacing bearings without also putting on new seals; and this may require purchasing new spacers. You could spend more than $100 per wheel to ensure they are safe. If there is a lot of play, pull the axle and check carefully for any hub damage, as you could spend at least another $200 to $300 for a replacement hub if the bearing bore is worn out.3. Steering-head BearingsThis bearing is most susceptible to pressure washing but can also be ruined by a poorly routed gas-cap vent hose. Standing in front of the machine, grab the bottom of both fork legs and try to move them back and forth, perpendicular to the fork legs. If there is any play, plan on new bearings and seals and at least another $100 investment. While you are at the front of the bike, see if the fork turns easily side to side with no binding. Also, check the steering stop. If the triple clamp or the tab on the frame are damaged, that is a sign of a big crash that might have damaged the frame.4. BrakesSqueeze the brakes and check their firmness. Mushy is bad and can indicate poor maintenance or even a worn-out master cylinder. Ka-ching! A quick look will tell you if there is any brake pad left, but you'll also want to check the overall system. Grab the caliper, especially the rear, and check for any side-to-side play. A bit is normal, but a lot can be dangerous; it may require replacing the sleeves or, in the worst case, buying a complete caliper. Also, check the rotors for straightness by spinning the wheel while holding something (a key will do) on top of the swingarm or on the front of the fork leg to see if the rotor is bent. Additionally, an extremely worn rotor is a sign of heavy use and can be a precursor to other, more-significant wear and tear on the bike.5. SuspensionWhile you won't be able to do a comprehensive analysis of the fork and shock, there are a couple of quick tests to evaluate the relative condition of these components. First, look for any obvious fork-seal leaks. Scan the bottom fork casting for any signs of oil buildup. On some bike brands, you can also slide the wiper out of the fork leg and inspect for buildup of mud and oil. Another important check is for worn bushings in the fork. With the bike on the ground, lock the front wheel with the front brake; and by pushing down and forward on the handlebar, you will be able to feel some freeplay if the bushings are worn. Make sure you have first evaluated the wheel and steering-head bearings as they will give the same feel. You can also do this by grabbing the bottom of the fork legs in the same way you tested the steering-head bearings. Expect to spend some major bucks to repair the fork if any noticeable play is felt during these tests. To check the shock, push up and down on the rear of the bike and note any damping. If the bike boings back up, steer clear, as the shock is probably worn out. Also check for freeplay at either end of the shock, indicating worn bushings. A shock rebuild can easily top $500, so be thorough in this evaluation.6. Swingarm PivotAnother bearing that is very susceptible to damage from the pressure washer is the swingarm pivot. A definitive test is to remove the shock and move the swingarm through its full travel, but most likely, the current owner won't allow you to do that much work. Nonetheless, sit on the bike and make the rear suspension move, listening for bad sounds. Also, with the bike on a stand, grab hold of the end of the swingarm and try to move it left to right. This will take some force, so have someone hold the bike; but if there is any freeplay, new bearings are in order, and again you're looking at give or take a C-note for repairs.

7. Suspension LinkageOn a KTM, just check the lower shock heim joint for freeplay, and figure that any movement equals another $100. On all other bikes with linkages, you may be able to hear, or even feel, dry and rusty bearings, though this is best done with the shock off. Ask the current owner about greasing service on the linkage, and better yet, pull one of the bottom bolts to check for grease and free movement. A badly neglected linkage system will not only seriously affect handling but also surely run at least a C-note to repair.8. Chain and SprocketsYou can figure that a front and rear sprocket and a good, quality non-O-ring chain will cost around $150 to replace. The quickest insight into relative chain life is on the teeth of the sprocket, especially the front. Look for thin, sharp teeth, with a hook on the front edge. This warns the chain is ready to go. At the rear, check the chain by trying to lift it off the sprocket.A brand-new chain will sit tightly between the teeth, while a usable chain will have up-and-down movement yet no substantial front-to-back clearance. Also note if there is any side wear on the sprocket, indicating chain misalignment, a bent chain guide, worn wheel bearings or possibly even a bent swingarm. Remember that a chronically overtight chain will ruin the countershaft bearing, so be sure to check the output shaft for any up-and-down play at this time.9. PowerplantCompetitive race bikes are now available with two distinct and very different engine types-two- and four-stroke-that require very different levels of expenditure to rebuild. The reality is that because of the extremely high levels of power output, the new generation of four-stroke race bikes not only requires maintenance at least as often as (probably more often than) current two-strokes but also costs more. Whereas a top end rebuild of a nonexploded two-stroke will cost a couple of hundred dollars, a top end job for a four-stroke race bike is even more. A four-stroke with a season of racing will most certainly need valve replacement and a new piston. If this is not done, chances are it will blow up or worse and easily require as much as a couple of grand to get back to running condition.We compared a serious but standard two-stroke (Honda CR125R) rebuild with that of a four-stroke (CRF250R). We figured the 125 would need a piston, a ring, a crankshaft, bearings, seals, a piston pin, a pin bearing and gaskets for a complete freshening; those parts added up to $378.92. We estimated the four-stroke would need a complete top end, including a piston, rings, gaskets, valves, valve springs, valve stem seals and a cam chain; those parts run $395. A cam-chain tensioner is roughly another $50. Other four-strokes may run more for parts, but the CRF has the most-frequent rebuild schedule.There are two quick ways to check the top end of a two-stroke. First, feel how much compression is available with the kickstart lever. There must be a very noticeable resistance, right at top dead center; and if there isn't, steer clear. Second, if you can talk the seller into letting you pull the exhaust pipe, look in on the piston through the exhaust port. With a flashlight, check the condition of the piston. There should be no vertical marks, and especially no shiny aluminum buildup, indicating a previous seizure. Note that this isn't definitive, as the piston can be seized on either side of the port and not visible unless you pull the cylinder; but you can get an idea of the wear and maintenance on the bike by assessing the condition of the piston. Dirt that has entered the engine will also show vertical marks; and a smooth, shiny surface on the front of the piston indicates a lot of use.On four-strokes, starting is the key indicator. As the engine gathers hours, the intake valves especially will tend to recess into the seats, with the sealing surface of the valve mushrooming out. This will decrease the valve clearance and eventually will cause difficulty in starting because of the tight valves. Also look for blue or black smoke exiting the exhaust when revving the bike. Blue smoke is the result of oil getting into the combustion chamber and indicates worn rings or valve guides and seals; and it means the top end is badly in need of service. Black smoke points to an overly rich fuel mixture and may also signal a worn top end, as the rich fuel mixture tends to wash the oil off the cylinder, speeding wear on the piston and rings. Check out the top end as closely as you can, since it is not cheap to repair.10. Transmission and ClutchThe internal engine parts are a little more difficult to get a true picture of, but you can get a good sense of the state of things by listening to the running engine and feeling the smoothness of operation of the shifting and the clutch. During your test ride, make sure the clutch fully disengages so you can put the bike in neutral when stopped, and note whether or not the engagement is smooth and progressive. A notchy feel tells of a worn clutch. During your test ride, also check to see if the clutch is slipping by shifting into a high gear then applying a lot of throttle. I can guarantee that a slipping clutch will not heal itself, and you could easily spend $100 or more to replace it. The transmission should shift easily and smoothly and, of course, not jump out of gear or miss shifts. Don't be timid on your test ride, as it's better to have the seller a little mad at you for abusing his bike than to buy a bike that needs $500 or more of transmission work.The bottom line is that virtually any brand of off-road motorcycle manufactured in the last five years can be a great bargain. The real keys are in how well it has been maintained and how hard it has been used. So be prepared to do a little research on a bike before handing out some major money on a mount that needs even more cash to be a safe and reliable ride. This way, you will avoid painful "buyer's remorse."