Is Motorcycle Exhaust Popping Bad? The Facts Explained

If you ride an older carburetor-style motorcycle, you might find yourself dealing with a popping noise during acceleration coming from the exhaust. Those who aren’t familiar with motorcycle mechanics might consider this a sign of serious issues with your motorcycle’s engine or exhaust systems. 

Motorcycle exhausts will pop when unburned fuel is detonated in the exhaust system rather than the engine. This issue is often the result of aftermarket exhaust systems or clogged carburetor jets. Tuning and cleaning the motorcycle carburetor can correct popping issues.

A popping exhaust on a motorcycle isn’t usually a serious problem, but correcting it can prevent related problems from occurring down the road. Read on to learn more about exhaust popping in motorcycles and how you can fix it. 

Why Does My Motorcycle Exhaust Pop?

There are a few different reasons why a motorcycle exhaust may make a popping noise during acceleration. Here are some of the potential causes (Source: MotoShark): 

• Aftermarket exhaust systems: Aftermarket exhaust systems may let extra air into the exhaust system compared to the stock or OEM exhaust. This can eventually lead to a popping issue with the exhaust. 
• Excess air in the exhaust system: The reason that aftermarket exhausts can cause popping is that they are high-flow systems, causing more air than usual to be flushed through the exhaust system. 
• Engine running lean: When your motorcycle exhaust is popping because the bike’s system is running lean, you’re also likely to experience other symptoms such as flat acceleration and a surge in the engine when cruising at half throttle. A lean-running engine can be corrected by tuning the carburetor. 
• Clogged carburetor jets: Another carburetor issue that can cause popping in the exhaust system is clogged carburetor jets. Cleaning the carburetor jets can correct the engine’s fuel-to-air ratio and prevent detonation of excess fuel in the exhaust system. 

All of the reasons the exhaust system on a motorcycle pops lead back to a problem with excess fuel in the exhaust system that ignites outside of the engine. 

What Kind of Motorcycles Have a Popping Exhaust?

Popping exhaust systems are seen most frequently on carburetor systems, so motorcycles that run into this problem tend to be older models. Motorcycles with carburetor motors may require more fine-tuning than newer bikes when it comes to adjusting the engine’s fuel-to-air ratio.

Can a Motorcycle Exhaust Popping Hurt Your Motorcycle?

Worried about a popping exhaust on your motorcycle? While it might sound like a serious problem, the truth is that a popping in your motorcycle’s exhaust system shouldn’t do any serious damage to your motorcycle’s exhaust other than causing a little bluing in the metal. 

The real issue with a motorcycle exhaust popping is if it indicates an engine that’s running lean. If you run your motorcycle lean, this can cause the engine to get hotter and stay hotter for longer periods. Over time, this can cause undue wear and tear to your motorcycle. (Source: New Rider Tips)

How to Fix a Popping Motorcycle Exhaust

The main suspect for a popping motorcycle exhaust is a poorly-tuned carburetor. The disadvantage of carburetor-based motorcycle engines over fuel-injected systems is that if the carburetor goes out of adjustment, it has to be fixed manually to maintain the engine’s performance. 

If your popping motorcycle exhaust is related to the carburetor, you’ll note that the exhaust popping occurs when the motorcycle is decelerating. 

To fix a popping motorcycle exhaust, perform the following (Source: ItStillRuns): 

• Note the RPMs where the motorcycle begins to experience exhaust popping. You may need to do some test rides and pay attention to the way the bike is riding to determine the exact point where the popping occurs. 
• Remove the carburetor from the bike’s engine. The procedure for removing the carburetor will vary from motorcycle model to model. Consult your owner’s manual to determine exactly how to remove the carburetor from the bike. The carburetor is usually located on the intake manifold of the motorcycle engine. 
• Disassemble the carburetor. Once the carburetor has been taken apart, clean each part thoroughly with a carburetor cleaner.
• Reassemble and reinstall the carburetor. Once the carburetor is cleaned, put the carburetor back together and put it back on the bike. After cleaning, the carburetor is ready to be fine-tuned.  
• Adjust the idle speed. Using the adjustment screw, adjust the engine’s fuel-to-air ratio until the engine can decelerate without the exhaust popping.  

If you don’t feel confident removing your motorcycle’s carburetor and fine-tuning it yourself, you always have the option to take your bike to a motorcycle carburetor specialist. Adjusting a carburetor can be tricky for novice mechanics, so sometimes it’s a task best left to the professionals. (Source: LiveAbout)

Final Thought

If your motorcycle’s exhaust system has begun to pop during deceleration, there’s no need to get worked up about it. At worst, this is a problem that may require a standard tune-up to correct. The problem is even simple enough that you may be able to fix it at home.