{"id":861,"date":"2022-10-14T15:18:51","date_gmt":"2022-10-14T15:18:51","guid":{"rendered":"https:\/\/wulfmoto.com\/?p=861"},"modified":"2022-10-14T16:18:42","modified_gmt":"2022-10-14T16:18:42","slug":"popping-on-deceleration-lean-or-rich-motorcycle","status":"publish","type":"post","link":"https:\/\/wulfmoto.com\/popping-on-deceleration-lean-or-rich-motorcycle\/","title":{"rendered":"Popping on Deceleration: Lean or Rich? – Motorcycle Mixture Problems Explained"},"content":{"rendered":"\n

Whether you’re into motorcycles or cars, we all love hearing our machines make popping sounds while decelerating. <\/p>\n\n\n\n

Those popping and crackling noises happen at random and remind you (and any people nearby) of the raw, untamed power that internal combustion engines can produce. Music to my ears. <\/p>\n\n\n\n

But does popping on deceleration indicate a lean or a rich mixture?<\/p>\n\n\n\n

Popping on deceleration can occur because of both lean and rich mixture – it’s very difficult to reliably tell which one is the culprit just from the popping sound only. With that said, the most common reason for popping on deceleration is a lean Air-to-Fuel mixture.<\/strong><\/p>\n\n\n\n

You can determine whether a lean or rich condition is the reason for your motorcycle popping on deceleration by simply looking at the spark plugs and the general symptoms of lean and rich conditions.<\/p>\n\n\n\n

But did you know that popping on deceleration can be a sign that your engine’s air-to-fuel mixture is incorrect? We’ll talk about that and more in this article.<\/p>\n\n\n\n

What Causes Exhaust Popping on Deceleration? <\/strong><\/h2>\n\n\n\n

Popping on deceleration can be caused by both lean or rich Air-to-Fuel mixtures. The most common reason for exhaust popping on deceleration is a lean condition.<\/strong><\/p>\n\n\n\n

A lean or rich condition can be a result of a vacuum leak, blown exhaust gaskets, or internal carburetor <\/a>problems. <\/p>\n\n\n\n

But what makes the engine pop on deceleration when the mixture is lean?<\/p>\n\n\n

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\"Hot
Exhaust headers get really hot!<\/em><\/figcaption><\/figure><\/div>\n\n\n

When the engine is running lean, it’s also running hot. The temperature of the combustion chamber is hotter than normal and the exhaust pipe (especially the headers) are hotter than normal as well. <\/p>\n\n\n\n

When you’re riding at, let’s say, 8000 RPM and suddenly release the throttle, all of that fuel used to keep the engine at 8000 RPM is now no longer needed and has to go somewhere. All of that extra unburnt fuel exits the combustion chamber through the exhaust port and splashes onto the exhaust headers. <\/p>\n\n\n\n

Since the exhaust is hotter than normal<\/a> from running lean, the unburnt fuel splashes onto the headers and ignites, producing that popping sound on deceleration. Normally, unburnt fuel would not combust inside the exhaust, but since the exhaust is very hot from running lean, it ignites the unburnt fuel. <\/p>\n\n\n\n

Is Popping on Deceleration Bad?<\/strong><\/h2>\n\n\n\n

Popping on deceleration can be very harmful to your motorcycle, especially long term. In most cases, a small amount of popping on deceleration will not harm your engine, as long as the timing is correct and the engine does not seriously overheat.<\/p>\n\n\n

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\"melted
This unfortunate piston melted from the heat.<\/em><\/figcaption><\/figure><\/div>\n\n\n

If the lean condition is very bad, your motorcycle’s engine can melt pistons or exhaust valves. No bueno. <\/p>\n\n\n\n

It’s always a good idea to take care of popping on deceleration before it becomes a big problem. <\/p>\n\n\n\n

Lean & Rich Condition Symptoms <\/strong><\/h2>\n\n\n\n

You can quickly determine the cause of your motorcycle popping on deceleration by looking at the most common symptoms of rich and lean conditions. <\/p>\n\n\n\n

Symptoms of a Lean ATF Mixture<\/strong><\/h3>\n\n\n\n