The seller, more often than not, tries to avoid spending a shovel full of cash for replacement parts when selling the bike. The seller is usually attempting to get the buyer to deal with any parts costs. You must come warned, and informed, about what to look out for on a used dirt bike. If you have performance knowledge and monetary value information concerning the machine you're interested in, it doesn't mean the bike should be purchased after you find and look at it. Thoroughly investigate the bikes condition - and save yourself money, time, and an immense abundance of grief! Here's what to do when you find a used dirt bike you wish to purchase from a private party.

Bring a Friend and Ask the Right Questions!
When dirt bike shopping, bring a friend with you that has some interest in dirt bikes. Better yet, bring a friend or trusted aquaintance that has dirt bike experience and knowledge. When inspecting the bike, your partner may have some different opinions and/or notice things that you may protentially miss or simply forget.

Ask the owner these questions:
"How often do you clean your air filter?" If the answer is, "After every one or two rides," it's a good bet the owner understands that proper air filter maintenance is important, and it may indicate the owner may be maintenance wise. If the answer goes something like, "Uh, air filter, uh... yea! All the time", go away. The bikes powerplant is shot.

"How often do you change the transmission oil?" If the answer is something like "Once every 2 to 4 rides," it's a good sign the owner believes in maintenance and the transmission/clutch internals are probably okay. If the bike is a 4-stroke, and the owner isn't changing the engine oil once every 250 to 500 miles, stay away from the bike. The oil in 4-strokes not only lubricates the engine, but the transmission too. It must be changed regularly or engine and transmission life are shortened considerably.

"Where and how often did you ride the bike?" This question can provide some valuable clues as to how the bike has been treated. If the bike has been ridden several times a week then raced on the weekends, you can bet the machine is worn and the machines remaining lifespan may be short. If the bike was trail ridden sporadically on weekends, it may be safe to believe the bike is capable of many more miles.

"Where do you store your dirt bike?" If the answer is anything but inside a building, forget buying it. Any bike kept outside didn't get proper care.

"Did you purchase this bike new, or has it been owned by others?" If the owner/seller doesn't know who used to own the bike, or how many owners that bike has been through, it's a sure thing that the maintenance history is completely unknown. You'll be gambling on the machines reliability if you purchase it. If you're talking to the bikes original owner, the only thing you'll have to worry about is how much the owner may stretch the truth. Try to buy from older owners. Be careful though! Sometimes "older" owners may be selling their kids MX bike.

"Has this bike been modified?" Be sure to ask what modifications were performed and why the owner, or owners, made the modifications. Do NOT buy a motorcycle that has been modified heavily! Especially if the owner brags of the porting work or other such high performance mods. These mods are bike killers, and the owner has probably ridden the bike hard. While discussing modifications, ask the owner what ratio and brand of oil was used for engine, and transmission lubrication. Ask the brand and type filter oil used. Question the fork oil useage and settings. The purpose behind these question is to gather the depth of the individuals knowledge of dirt bike care. What they say to your questions isn't the realvpoint. One should find out what they know. Again, this isn't foolproof, but it can certainly indidicate the owners care of the motorcycle.

Perform these checks on the bike:
If it's possible, place the bike on a stand. (Bring your own bike stand.) Once the bike is on the stand, get behind the bike, grasp the rear wheel, and try to wiggle it from side to side. If it wiggles or moves any, the bearings holding the swingarm and/or rear wheel on the axle are probably bad and need replacement. This could spell dollars to replace or fix. Move to the front of the bike, kneel down and grab the front wheel. Do the same to the front wheel and note any movement. If there's movement, there are bearing problems. Spin the front and rear wheels while the bike is on the stand. If the wheel wobbles while spinning, the rim is bent. Often, a person can not tell if the rim is hopelessly bent just by looking at it.

Here's a check to perform that even experienced used dirt bike buyers forget to do. Take the radiator cap off and look into the radiator (if the bike is water cooled) and look at the radiator fluid. If the radiator fluid is anything but green, the owner, or owners, have never changed radiator fluid and there could be internal radiator passages that are blocked, thereby reducing the bikes engine cooling capacity. If you don't see any radiator fluid, consider this a red flag warning and start asking more questions.

Start and ride the bike. (If the seller won't let you ride it, don't buy it.) When riding the bike, run the machine through every gear and be sure every gear works! If the bike has a 5-speed transmission and you can only shift 4 times, the machine has big time transmission problems. Note any excessive vibration. If there is enough vibration to be felt through your arms and shoulders, the bike has bearing problems in the cases. (This statement does not apply to any Yamaha YZ 490.) Problems such as those just described are expensive to remedy, and its best to walk away if you note these conditions.

When riding the bike, listen for any loud noticeably loud metal to metal 'slapping' or 'ringing' noises. These noises may indicate cylinder or piston problems.

Bounce up and down on the seat. If you hear loud squeaking noises, or the bikes suspension sticks while bouncing, there are suspension linkage problems. Repairing suspension linkage problems costs money. Sometimes it costs vast quantities of money.

Look closely at the forks and rear shock. Look for oil seepage or outright oil leakage on both components.

Take a narrow strip of white construction paper and dip it in the oil filler hole. If the paper comes out with creamy/white looking oil, the bike has a water pump seal leak. If the oil comes out grey, don't write off the bike completely. The bike probably has aluminum clutch plates and these plates contaminate the transmission oil very easily. If the oil comes out black, the owner probably does not change transmission oil very often. Lastly, if the oil comes out tan, either everything is okay, or the owner just changed the transmission oil to fool the prospective buyer.

If possible, take off the flywheel cover on the engine case. Once off, the covers inside and the area surrounding the flywheel/magneto arrangement should be dry. If it's not dry, find out by looking or feeling if the wet stuff is either water or oil. If it's water, the magneto cover was leaking and there could be rusty magneto components lurking in there. If it's oily, the crankshaft seal is leaking and requires replacement. This spells money.

Make sure the frame is checked carefully. Look for hairline cracks in the metal around welds. Place the bike on its side and inspect the frame rails under the engine. Are these rails mashed, rusty, or filled with holes?

Here are some "Rules of Thumb" for parts replacement costs and labor charges: