What do I look for when buying a used dirt bike?

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What do I look for when buying a used dirt bike?
That is often a loaded question because every bike has different issues.
This is a general list of things to look for on every dirt bike.

Does the ad say something like "Just needs the carb adjusted"
Or "Runs great, just needs a little work."
Or, "It's a easy fix, I just don't have the time to fix it"
WARNING!!
These ads are usually totally bogus..
How long does it take to adjust a carb?
It will take longer to warm the bike up then adjust the carb.
If it's a easy fix, ask a friend to do it for you.
If your busy any good friend will help you out, especially a riding buddy.

Now, what to bring with you to look at the bike.
If you have a bike stand, bring it.
If not a 3.5 gallon pale and a short piece of 2X4 will work most of the time.
Bring some basic hand tools for removing the plug, seat, and checking the clickers for the suspension.
If you have it a compression gauge that's good but a leak down tester is better
A couple of shop rags and a can of carb cleaner for inspecting greasy area's.
You might also bring a clean pan and a funnel.

If the seller tells you that work has been done, don't be shy about asking for receipts.
They don't always tell you the whole story but they are further proof that a seller is honest.

Look at the general appearance of the bike.
What do you see?
Is it dirty, worn looking, or does it have ill fitting parts?
DANGER!
If it's dirty it could be a signal of poor maintenance.
Not always but it's tough to maintain your bike if it's filthy all the time.
If it looks worn that is usually a sign of it being worn out.
If the parts don't look like they fit correctly, they may not be the correct parts.
This brings up another point, MAKE SURE THE BIKE IS THE YEAR BEING ADVERTISED!!!!

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Make sure that the bike is the year the seller says it is and make sure it has the correct engine.
You would be stunned how often the bike is older then advertized and the engine does not match the chassis.
I have spent quite a bit of time putting together bike ID charts.
But first, here is a link to figuring out what year your bike is.
http://www.oem-cycle.com/Find_Out_Year_of_bike.shtml

Here is a link to a page that has links to engine ID's and parts interchange:
http://www.oem-cycle.com/BikeIdentification.shtml
Scroll down and select your bike.
The rest is self explanatory

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Put the bike up on the stand or the pale and spin the wheels.
Do they wobble up and down or side to side?
Most manufactures allow up to 1/16" up or down and side to side.
Now, grab the spokes and squeeze them together. Are they loose?
Forget about tightening them as most of the time spokes are froze.
Look where the spoke nipple goes into the rim.
Is the rim wallered out?
If so it's replacement time
Look all along the edges of the rims for cracks.
They can be hard to spot depending on the condition of the rims.
The more scratched up the rims the harder cracks are to spot.
How do the bearings feel?
Smooth or rough?
While you are there, look at the brake rotors, are they worn or wobbly? If so they need to be replaced.
And the sprockets, are they sharp and worn? Replace them as well as the chain if they are.
Take a hard look at the chain, any kinks, rust or visible wear? If so replace it.

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While the bike is still up in the air, try to lift the rear wheel up and down.
Is their some dead play with no dampening?
If so, chances are the swing arm linkage bearings and or the swing arm bearings are worn out.
Look carefully, it may even be that the shock bushing/bearing is bad.
If it's real loose you may even have worn out linkage housings or swing arm which can get expensive.

Check the frame for any cracks or non factory welds.
Look at the front of the swing arm where the chain slider is.
Is the swing arm worn? I've seen them worn to the bearing inserts..
Look at the rear brake caliper mount, try to wiggle it.
If it's sloppy you may have to replace the mount or repair the swing arm depending on the style you have.
Another way to test it is to hold the rear brake on and then try to turn the rear wheel forward and back.
If it's loose you will be able to spot it quickly.
Try to loosen or tighten the chain tension adjustment screws.
Often they are frozen.

While your there, take a hard look at the chrome plating on the shock and the forks.
Is there any rust or pitting?
Are the chrome surfaces dry or weeping oil?
Weeping oil equals new seals at a minimum.
Also, look at the rubber stopper in the rear shock?
If it's missing or crumbly looking then it needs to be replaced.
In order to replace the bump stop you will have to disassemble the shock.
Also, check the rebound and dampening adjusters if there are some for the model you are looking at.
The adjusters should turn smoothly but a little stiff and generally click into position.
Look carefully at the fork alignment.
Do they appear to be offset?
Then they are most likely bent.
You can double check by putting the bike on a stand and removing the front wheel.
Then sight across the forks.
They should be parallel with no misalignment.
Also look for fork tube discoloration.
If you see dark streaks then most likely the tubes got hot from lack of oil and plan on a full rebuild.
Remember, any deformity of the chrome finish likely means a problem.

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While you are looking around, look at the tires and see if there is checking or cracks...
The tread life should be clearly evident
Then, take a hard look at the brakes.
Is there any signs of leaking?
Are the pistons or the bolt that holds the pads in rusty?
Are the pads thin?
Check the brakes hoses for wear or checking.
Then feel the brakes.
Are they firm or mushy?
If the master cylinders have windows look at the fluid color.
Are they dark or clean, almost clear?
Look at the brake hoses.
Are they worn or have kinks?
Is the outer wrap coming off?

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Now take the bike off the stand and stick your head under the bike and look at the cases.
Any repairs?
Any leaks?
If it's dirty, clean it up a bit to be sure.
If there are leaks, look around to see where the leaks are coming from.
It's amazing how well dirt and grease will hide JB Weld.

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Here is something that quick and easy but can tell you a lot.
Pull the seat off and look into the air box.
Is it full of sand and dirt? If so BEWARE!
This could be a sign of a lack of maintenance.
Is there any tears in the filter or is the filter not fitting tightly?
Remove the filter and feel into the rubber boot.
If you feel any grit.... Run away fast.....
Since you have the seat off take a hard look at the sub frame.
Any cracks, non factory welds, or non factory bolts?
If so it may be a sign of poor repairs, or impeding repairs..
Look at the bottom edge of the seat for tears in the cover.
Wiggle the mounts to see if they are loose.
Check the pan for cracks.

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Radiators are often over looked.
Besides removing the cap and checking for fluid color and cleanliness, look at how the radiators mount.
Are they bent?
If so, how do the shrouds look.
Often shrouds are broke when the radiators are bent.
Are all the mounts there?
Look hard for zip ties
Look for signs of leaks.
Often, sellers will use products like stop leak instead of replacing the radiator.
Check the hoses for cracks or checking.
Again, this can be tough if the bike is dirty.
When you pull the cap look at the underside of it.
Is the rubber seals good or are they cracked or checked?

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Take a look at the engine case that holds the sprocket guard.
Are the mounting towers cracked, broke, or missing?
If so it will need to be repaired or the next time you loose a chain you could destroy the case.

Now, drain the oil into your clean pan and check the oil for color and debris.
And, check the threads for the oil plug.
If they are jacked up that means another repair

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Gas tank...
Check the petcock to make sure it operates smoothly.
Inspect the cap.
Make sure the rubber seal is good.
Also, make sure the breather tube is good and unobstructed..
Now, check those bolts that hold the radiator shrouds on.
Many times they are froze to the gas tank inserts and then you have problems...
And smell the gas...
Does it look like Bryant shrimp inside?
Yeah... Mo money to fix if it does...