How To Check For Motorcycle Exhaust Leaks?

This article focuses on identifying and fixing motorcycle exhaust leaks. 

Exhausts, like any motorcycle part, can get damaged and start leaking. This could be because the bike has been in an accident where one of the pipes was cracked. It could also be a loose gasket or bolt. Small stones and road debris kicked up by the wheels could also make tiny fissures in the exhaust wall. 

If you suspect your exhaust is leaking, it is relatively easy to check. There are a couple of usual suspects when it comes to exhaust leaks. You can check if the exhaust exhibits any of these signs and then fix them appropriately. 

After almost a decade of working on motorcycles, we think we can help you solve just about any problem you might encounter. Exhaust leaks can be quite concerning, as they rob your bike of power and efficiency. It is best to get them fixed ASAP! 

Keep reading for more info on exhaust leaks and how to check for them. 

Most Common Signs Of An Exhaust Leak

Below, we outline some common signs that your motorcycle exhaust may be leaking. 

Distinct Ticking Noises

This will most certainly allude to a leak in the exhaust manifold. If you get a slight ticking noise from the part of the exhaust closest to the engine, it could signal an exhaust manifold leak. 

Loose Exhaust Bolts

Exhaust bolts need to be tight and secure to withstand the high pressure of gasses inside the exhaust. Check if one of the bolts connecting your header pipes to the engine is loose. If you notice rust or corrosion on one of these bolts, it is good to get them changed ASAP. 

Faulty Gasket

If you aren’t familiar with a gasket, it is simply a component between two different engine parts, say the head and the block. In the case of exhausts, there is a gasket between the header pipes and the cylinder head. A gasket can be made of various materials such as heat-resistant fibers, rubber, metal, or other composite materials. 

The sole purpose of a gasket is to fill the space between two engine parts and prevent leakage. If damaged, these gaskets can result in exhaust gasses leaking out of the engine.

Loud popping and backfiring

Another dead ringer for an exhaust leak is loud popping and backfiring. A little bit of popping from the exhaust is pretty normal, especially in older vehicles. However, very loud popping and backfiring, and lots of it could signal an exhaust leak. 

Louder Idle

If you notice your motorcycle idling louder than usual, it could be due to an exhaust leak. The noise might die down once the bike warms up, but it will still be pretty noticeable. 

Is An Exhaust Leak Bad For My Motorcycle?

Make no mistake. An exhaust leak could potentially be disastrous for your motorcycle engine. The effects of an exhaust leak vary greatly. Find some of the most concerning symptoms of an exhaust leak below. 

Overheating 

Exhaust leaks cause the exhaust system to overheat because the exhaust gasses are not being ejected properly. These high temperatures will cause unburnt fuel in the exhaust to combust, resulting in loud pops and backfires. 

Discoloration of the exhaust

An exhaust leak could cause abnormal discoloration of the exhaust. The higher temperatures will cause the metal surface of the exhaust to oxidize prematurely, resulting in the ‘blue-ing’ of an exhaust. 

Harm to mechanical components 

An exhaust leak will cause damage to the various engine and exhaust components. These parts are designed to withstand extremely high temperatures. Still, extended exposure to such high heat levels will reduce the lifespan of sensitive engine components. 

Reduced performance

Exhaust leaks will cause your motorcycle to feel sluggish and underpowered. This is because of the higher temperatures and because the exhaust gasses are not being ejected as efficiently. 

The bike will be slower to accelerate, have a reduced top speed, and overall, won’t be as fun to ride as before. 

Worse fuel mileage

Your motorcycle’s fuel mileage will also take a hit if the exhaust is leaking. The abnormal emission of exhaust gasses reduces the efficiency of the engine. Expect to get fewer miles to the gallon than if your exhaust wasn’t leaking. 

How To Fix an Exhaust Leak Yourself

With exhaust leaks, we recommend getting them fixed by a professional. That said, it is possible to fix an exhaust leak at home. 

Step 1: Locate the leak

The first step to fixing an exhaust leak yourself is to figure out exactly where the exhaust is leaking. This can be done in a couple of different ways. Inspect the pipe visually. Look for cracks, holes, rust, or other damage to the exhaust pipe itself. 

Make sure you inspect the entire pipe and check the underside of the exhaust. Tiny rocks, speed bumps, and even rust can make minuscule cracks in the metal. 

If you don’t find any leaks just by looking at the exhaust, the next step is to fire up the engine and run your hand over the exhaust pipe. 

Don’t worry about burning yourself, as the engine won’t be that hot for the first couple of minutes. Still, it pays to be careful. You’ll be able to tell where the exhaust is leaking by where you feel the gasses escaping. 

Finally, if you still can’t find the leak, try using a soapy water solution. Prepare a solution of water and soap. Fill up a spray bottle with the stuff and spray it liberally over the exhaust. Make sure the engine is running and inspect the exhaust pipe closely. 

If there is a leak in the exhaust, you will see tiny bubbles start to appear on the surface of the exhaust. Spray the area where you suspect the leak is located some more to make sure. If you see more bubbles that keep getting bigger before popping, you just found your exhaust leak. 

Step 2: Plug the leak

Here are a couple of different ways of plugging an exhaust leak. 

1. Epoxy

Now that you’ve found the pesky exhaust leak, it is time to seal it up. One common method of sealing an exhaust leak is epoxy. This works well for very small leaks but not so much for big gaping holes. 

Follow the instructions that come with the epoxy and apply it evenly over the affected area, making sure you wait long enough for it to dry before starting up the engine. 

2. Exhaust Tape

If the hole is larger, using exhaust tape might be the answer. Exhaust tapes are specifically designed to withstand high temperatures and work well for sealing leaks. You can find a couple of different types of exhaust tapes that are pretty effective. 

Regardless of which one you get, we recommend putting at least two layers of tape over the leak. Make sure the tape covers at least 2 inches to either side of the leak for better sealing. 

3. Stainless Steel Clamp

One more method of sealing motorcycle exhaust leaks is to use a stainless exhaust clamp. This method only works if you find an exhaust clamp that can cover the entire hole or crack. If you can find one that fits, it should contain the leak quite well. 

4. Aluminum Patch

Lastly, if the crack is pretty large to the point that a clamp won’t cover it, you can seal the exhaust with a patch of aluminum. These are available in a roll form and come in various widths. Just take as much as you need, stick it onto the crack, and add some epoxy to the edges for an even more secure fit. 

This method is ideal for larger exhaust leaks, and you can make it even sturdier by adding an exhaust clamp on top of the patch. 

Conclusion

Exhaust leaks are pretty common and can be caused by basically anything: small rocks, road debris or accidents, and large bumps in the road. Thankfully, locating and plugging an exhaust leak is pretty easy to do. All you need is a couple of extra materials and a can-do attitude!

Author
Hugo Alais

Hi, I'm Hugo, I'm a motorcycle enthusiast who’s been riding for the last 10 years. I'm passionate about all things motorcycles and started Bikes Future to help other riders make the right motorcycle moves. I ride a white Kawasaki Ninja 400. You can find out more about me and my experience with motorcycling here.