Does Slip-On Exhaust Damage Engine?

Slip-on exhausts are becoming popular with the younger generation. They are easy to install and often give an aesthetic look to a motorcycle. But there’s a catch. There will be a decrease in the backpressure.

That is because slip-on exhausts use a less restrictive muffler. So, will it damage the engine? The short answer is no. A slip on exhaust systems will not damage your motorcycle engine.

Exhaust backpressure is the amount of pressure created by the flow of exhaust gasses that are forced by the engine to push on the exhaust system. The less restrictive a muffler, the lower its backpressure.

Stock exhaust is very restrictive because they have to follow certain rules and guidelines regarding emissions and noise pollution. On the other hand, an aftermarket slip-on doesn’t have to follow those rules.

However, too much decrease in back pressure can cause damage to the engine, so for this reason, most bikes use restrictive mufflers. So, what’s the verdict here? Will adding a slip-on exhaust damage the engine or not? Let’s find out.

Can An Exhaust Cause Engine Failure?

If we are talking about a slip-on exhaust, there is no point worrying about engine damage. However, if you are planning on a full exhaust upgrade, then there is a good chance this modification can cause engine failure.

Can An Exhaust Cause Engine Failure

To understand how an aftermarket motorcycle exhaust can cause harm to your engine, you will have to first understand the basics of an exhaust system.

Understanding Exhausts

The exhaust is not just a single component. There are multiple stages in an exhaust system. The first is the header. If the bike is a single cylinder, then there will be one header pipe. And if there are two cylinders, there will be two header pipes.

The pipes are then connected to the collector, also known as the exhaust manifold. After the collector, there is the middle pipe. This is where the catalytic converter is located. Also, the middle pipe connects the collector to the muffler.

If you want only good sound, then you should be worried about only one thing, and that is replacing your muffler, aka the slip-on exhaust.

Back Pressure & Full Exhausts

Your whole exhaust system depends on backpressure. When the exhaust smoke comes out of the engine and it’s traveling through the header pipes, the collector, catalytic converter, or the middle pipe, and the muffler, there is a level of backpressure being created. 

This pressure is essential for the air/fuel mixture of the engine. When you replace the muffler along with the catalytic converter, the exhaust system becomes a free-flow exhaust system. This means there is almost no back pressure involved.

Back Pressure & Full Exhausts

In that case, what happens is that the exhaust gasses come out too fast out of the cylinder, and the air-fuel mixture becomes lean because too much air gets to the cylinder. This lean mixture is bad for your engine.

Your engine will run much hotter than usual, so that is where an aftermarket exhaust can harm your engine.

Changes Made To A Bike After Installing A Slip-On

Slip-on exhausts won’t make your bike go faster or more powerful compared to full system exhausts. There will be no change in the horsepower either. Slip-on will, however, improve the way your bike looks and sounds, and they might even save you some weight.

Changes Made To A Bike After Installing A Slip-On

If you don’t want any harm to your engine, simply just take out the muffler, put an aftermarket muffler but do not touch the middle pipe, which has the catalytic converter.

What About Full System Exhaust?

If you want performance, like gaining in horsepower, torque, and all of those figures, you will need a full system exhaust. A full system exhaust has a complete kit right from the header pipes to mufflers.

If you install a full system exhaust, you will have to do an ECU remapped to your engine. If you do not do that, the air and fuel mixture will become too lean, and your engine’s exhaust valves will get burnt. This can easily cause harm to your engine.

Full System Exhaust

However, the same can’t be said for dirt bikes. A dirt bike exhaust system is a complex and intricate system consisting of pipes, mufflers, and other parts that help remove heat from the engine. If you want to add one, contact a professional first and have them install it for you. 

How Do I Know If My Exhaust Is Damaging The Engine?

When it comes to motorcycles, you will find that there is a lot of maintenance that needs to be done. One of the most important things that you need to do is to make sure that your exhaust system is in good condition.

If the bike is in a lean condition, the exhaust might be damaging the engine. This is because if the engine gets too hot, it will start to crack and warp, which can lead to expensive repairs.

How Do I Know If My Exhaust Is Damaging The Engine

If you notice that your motorcycle is starting to make strange noises or has started to run poorly, this could be a sign of damage from an exhaust leak. There are several ways to know if your exhaust is damaging your motorcycle’s engine:

  1. First, start by consulting a professional. They will be able to tell you what the best course of action is.
  2. You can check if there are any signs of corrosion on your bike’s cylinder head or other parts of its engine.
  3. You can listen for strange sounds coming from your bike’s engine; or
  4. You can use a smoke test kit that uses a little smoke generated by a cigarette lighter to see how well it works in detecting damage to your bike’s engine.
  5. You might hear a popping sound when you start your motorcycle or when you accelerate. A number of factors can cause this, but it is mostly due to the exhaust leaking into the engine and causing damage.

Also, check for any signs of damage to the bike’s engine or exhaust system. If you see any signs of damage, then it might be time to replace the damaged parts with new ones.

The last thing that you should do is turn off your motorcycle and start it up again. If there are no problems after starting up, then the chances are that your exhaust isn’t causing the problem.

Will Installing A Slip-On Muffler Damage My Harley Touring Bike Engine?

Harley-Davidson motorcycles are known for their powerful engines and loud sounds. Even with their stock motorcycle muffler, these bikes are pretty loud. That is why most people go for a bike silencer or a slip on.

If you install in Harley Touring, it will not damage the engine, but it will make the bike even louder. Note that slip-ons are great for low-volume bikes, but they don’t have the same power output as a full system.

Will Installing A Slip-On Muffler Damage My Harley Touring Bike Engine

A full exhaust system or a true dual exhaust is preferred for high-performance motorcycles that need more power, torque, and better fuel efficiency.

Final Words

Slip-on exhausts come with instructions on how to install them, and it is important to follow those instructions from the beginning if you want to avoid damaging your bike. If you have any doubts about installing your slip-on, consult a professional who can help you out.

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