De-cell Pop

[NorthAlabamaSpyder]

2016 F30s with Lamonster cat deleat pipe and big city baffle with factory muffler. Has a pretty bad de-cell pop to it. Is this normal or should I look at a fuel controller or something? Have not checked plugs yet. Thx in advance

Bruce

 

[Deputy56]

decel pop

Popping on decel is a lean condition.

 

[jwulf74]

My low cost fix is just applying a super small amount of throttle on decel/braking... keeps the pops down...

 

[KX5062]

A fuel remap is the only sure-fire way to prevent the popping you are experiencing, given your current configuration. However, you could try a total BUDS reset and let the system relearn the fuel mapping. That's not certain, because a lot of motorcycles computer systems are preset at the factory to operate with the factory intake and exhaust configurations and can only make small adjustments for altitude and ambient temperature. Thank you EPA.

 

[PMK]

Decell pops in the modern fuel injected engine are not truly indications of lean condition.

Granted, the exhaust leak is always a possibility so I won't discuss that.

The modern fuel injected engine is loaded with sensors and is expected to obtain efficiency. One method to reduce fuel consumption is to have the computer sense a closed throttle, and with that, if the engine is being overdriven by the rear tire, no fuel is needed to sustain the engine to keep it running. As the machine slows down, the overrunning also slows. As the computer senses the engine will stall, it begins to add slight amounts of fuel to sustain it. Often, these blips of fuel, are ignited but also sent into the exhaust system, giving that pop sound. Chances are, if you reinstall the cat, the symptom still exists, however the added baffling will subdue the sound.

The person that mentioned add a slight amount of throttle, yes that works, since the computer is not seeing a closed throttle and is being told to rev the engine up.

 

[bruiser]

2016 F30s with Lamonster cat deleat pipe and big city baffle with factory muffler. Has a pretty bad de-cell pop to it. Is this normal or should I look at a fuel controller or something? Have not checked plugs yet. Thx in advance

Bruce

Did you do the 15 minute run in when you added the cat delete? The 1330 does have a tendency to pop on decel with the cat delete since it has less backpressure.

 

[DGoebel]

My low cost fix is just applying a super small amount of throttle on decel/braking... keeps the pops down...

Thanks JWulf, ever since you posted this (in this thread or a different one I can't recall) I've been successfully applying your technique and have quit looking for a 998 V-twin baffle. It works great!

 

[PMK]

Thanks JWulf, ever since you posted this (in this thread or a different one I can't recall) I've been successfully applying your technique and have quit looking for a 998 V-twin baffle. It works great!

Exactly, the engine is not having the fuel flow at 0.0 during throttle off decell. By keeping a slight amount of throttle applied, the computer does not go from zero fuel to blips of fuel to keep it running. With a partial throttle, you are commanding the engine to run above idle during decell.

Other than noise, the pops essentially are harmless to the engine or machine.