How to stop white smoke from dirt bikes & Why it’s happening?

You have started your bike and what you see, it’s smoking. One question strikes your mind, is it normal Or my bike is burning? Somehow smoking at the beginning may be okay but not always.

Also, you need to see what color is of smoke. If it is white and now you wish to know that how to stop white smoke from dirt bikes then stop getting panic, I’ll tell you why this is happening?

The simplest answer is your dirt bike is burning something which is neither gas nor air. Or you are starting your bike after so long, it may be released white or other colours of smoke & so many reasons are there behind exhausting smoke from bikes.

Here, you will see the whole causes and their solutions too. 

Different Smokes from dirt bikes & their meaning

The main and the most common behind the smoke is piston rings if it comes from the exhaust of dirt bikes.

Actually, the piston separates oil & air-fuel to avoid mixing which can lead to burning.

When it stops working, both oil & air-fuel get mixed in the combustion chamber and combined together, hence releasing bad smoke which can be either white, blue or black.

As you are asking how to stop white smoke from dirt bikes, first you have to know what kind of smoke a dirt bike can cause. I’m listing below the smoke types and their meaning. 

Do you want know about red exhaust then read our article why does dirt bike red exhaust?

White Smoke:

If you see white smoke coming out from the exhaust, it can’t be really smoke. It can be steam & fixed just by adjusting the engines.

When you cold start your bike, white smoke would come out from the end of exhaustion. It’s completely okay, just vapours formed by combustion.

Once you start your dirt bike and still produce white smoke, then there will be something messy.

There can be gasket insufficiency or fissure cylinder including blockage due to overheating.

The head gasket is used to maintain the separation of oil & coolant systems, also connecting with the cylinder head & combustion chamber. If it’s not working well then coolant will enter into the cylinder. 

White smoking will depend how much leakage is there in the gasket. If it’s small it can be fixed easily, but if the head gasket is strictly failed you won’t be able to fix it alone. 

Black Smoke:

Such kind of smoke produces due to malfunctioning in the ratio of air-fuel and lubricant. When the mixture of both will be high, black smoke will be detected in the exhausting, it happens when the air-fuel ratio will lower the spark’s ratio. 

The main reasons behind this issue can be leaking in fuel injector, blocked fuel pipe, dirty air filter which restrict the pure air passing through the combustion chamber. 

Black smoke can be occured when a small amount of fuel in a combustion chamber pushes out the unburnt fuel from the exhaust which converts this fuel into black smoke.

Gray Smoke:

Such smoke detects unwanted mixing of foreign oil with the air-fuel mixture which results in grey smoke. It shows bad effects on cylinders and combustion of air with fuel. 

It occurs when valves and piston seals don’t work well or we can say fail to separate unwanted fuel.

The damaged valve allows the fuel to reach up to the head and starts burning in the form of black smoke. Or if the piston is damaged it will allow the same to reach its way upward from the crankcase. 

Gradually this situation makes the compression power low and increases pressure within the crankcase. 

When the power output is turning in an engine, it needs more pressure in each part to start the dirt bike and hence push out the gray smoke. 

I have dealt with all kinds of smoke along with their causes. Let’s move to the next one where we will see how to stop white smoke from dirt bikes. 

Why does white smoke come out from a 2-stroke dirt bike?

Let me clear you why white smoke comes out from a 2-stroke dirt bike. This happens when petrol mixes into the fuel tank directly, and then petrol including fuel starts to burn together to form white smoke. 

White smoke always indicates incorrect ratio of fuels or excessive oil in the tank. 

What causes white smoke from a 4-stroke dirt bike? 

White smoke from a 2-stroke dirt bike means leakage in the engine oil directly into the combustion chamber where fuel is already burning will be mixed up with the engine oil. 

When both will mix together, they both start burning and this burning mixture releases white smoke. You may have changed your piston rings or not fixing in a good manner. 

How to stop white smoke from dirt bikes?

You can fix white smoke easily at home, but if you can’t do it, never try just for a fun. This mistake can put you in the worst condition. As we have discussed above causes, now we will see how to stop white smoke from dirt bikes. 

Check Temperature:

You need to to see the temparture level of your bike, as it’s an important fact for the smoke.

If the temperature is below 50° F, it means you haven’t started your bike for a long time.

White smoke at this time is normal, however, when the temperature reaches above 50°, there shouldn’t be white smoke anymore. If it still smoking, there could be water in the engine. 

Audit Whole System:

Overheating of the bike may be increased due to Seals, Pistons, and head of cylinder play of and let go the smoke out of finish point. Or any damage can be possible in the above system parts, change them or repair if you are expert in it. 

Although it’s showing too easy repairing process, be aware of fixing it. If you do even a minor mistake, which can be able to destroy the whole bike. If you know the whole connection and also what should be used to resolve the problem, go ahead otherwise I would like to say prefer the repairing centres. 

How to Fix Black Smoke From Dirt Bikes?

I guess you understand the reason behind black smoke from the dirt bikes, now know the solution to fix it one by one. 

Check Air Filters:

When the air filters are blocked this leads to a lack of air supply in the engine, then fuel starts burning, and this can be one of the reasons behind the black smoke. Check it once is there something stuck in the filter, clean it or replace it with the new one. 

Inspect Piston Rings:

Cracked Piston rings filter the fuel, but if it’s damaged can allow other fuels to mix into the combustion chamber. Make sure this would be in good condition, or if it’s defective, black smoke will be released from the exhausting point. 

Use Fuel Preservative:

You can add fuel preservatives to avoid pressure into the cylinder and combustion chamber. It will increase the performance of your engine. Ensure that the additive is of good quality. 

Black smoke isn’t always dangerous, it could be normal if you haven’t changed your fuel or not using a good fuel additive. 

How to Resolve Gray Smoke From Dirt Bikes:- 

Come to the last kind of smoke from dirt bikes, you have seen it earlier how it causes or why this occurs. Let’s know the process to avoid gray smoke. 

Examine Spark Plugs:

If your dirt bike is releasing grey smoke, examine the spark plugs. There can be cut or damaged in the plugs, replace it quickly.

or if you spot black soot on the spark plugs, it means something wrong in the combustion chamber or high mixture of fuel & air. One more thing you can notice shiny wet black film over the plugs, which means excessive oil has reached upward. 

Ensure Valve & Piston In Good Condition:

See whether valve seals & piston rings are in good conditions, or they may be loosely fitted. If it isn’t at its place can lead-grey smoke or show adverse effects on your dirt bike’s engine. 

These two steps will pick out the gray smoke from your dirt bike and within minutes, there will be no smoke. 

Note:- If the whole technique won’t work for your bike, you better visit the repairing centre. They will definitely find out the actual reason and clear up them quickly. 

Suggestion To Avoid More Damage:-

If smoke is coming out from your dirt bike, you need to follow a few points. As you know how to stop white smoke from dirt bikes, but if you won’t maintain it, your bike will be damaged more. 

  • If your bike keeps smoking, don’t ride it until the smoke completely vanishes. 
  • Don’t try to repair your dirt bike if you don’t have an idea about its part. 
  • Keep checking air filters, combustion chamber, gasket pipes to avoid any damages. 
  • Visit the professional bikes repair centre whenever you need to repair it. 
  • Always use quality based fuel else any foreign lubricant can lead to smoking. 
  • If you stick to the above-mentioned suggestions, a dirt bike will have a longer life. Even if you know how to stop white smoke from dirt bikes can’t make 

Bottom Line

I hope you find it helpful and by the time now fixed it as well. So, how’s today’s post, “How to stop white smoke from dirt bikes and why it’s happening”, don’t forget to tell us about our article in the comment box.

Smoke from the bike can be normal or damaging something on the side. If you like our post and want to get regular updates, you can subscribe to our newsletter. 

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Thomas A. Talley

I’m Thomas. Since childhood, I am fond of bikes and hence dirt bikes are my passion now. Ever since then, I’ve been giving advice to the beginners and this has become my hobby.

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