Popping & misfiring normal?

[Black Pig]

When I am working down through the gears, or just slowing down, I get lots of popping, banging and misfires once I shut the throttle off, is this normal?

 

[Ex-Rocket]

Didn't know what model you had until I checked profile. Are we talking about a 2008 GS? No, popping & misfire is not normal. This could be an indication of a lot of things, like bad gas, vacuum tubes at throttle bodies, bad spark plugs and the list goes on. Did you do anything to the bike before it started popping and misfiring? We probably need more information to give you a more detailed answer to your problem.

 

[Black Pig]

Oops sorry, no the GS runs a treat. It's this new F3 I have bought that does it. More pronounced now I have a two brothers exhaust system on it..

 

[asp125]

If you have replaced the exhaust you might need an ECU change. You may need to remap your fuel mixture. Power Commander might solve the issue.

 

[BajaRon]

Oops sorry, no the GS runs a treat. It's this new F3 I have bought that does it. More pronounced now I have a two brothers exhaust system on it..

You answered your own question. It is the 2 Bros exhaust. You'll probably have to richen up the mixture to get it to go away.

 

[Ex-Rocket]

:agree: Also if you have a cat delete along with a two brothers exhaust, a fuel map through Power Commander will help things.

 

[Black Pig]

It was doing it before the TB exhaust was fitted, it has been doing it since new. It's just much louder now

 

[Easy Rider]

When I am working down through the gears, or just slowing down, I get lots of popping, banging and misfires once I shut the throttle off, is this normal?

Yes. IF you have messed with the exhaust system so that it makes more noise.
Noise is noise. Get used to it.

Otherwise, no absolutely not.

 

[Black Pig]

Yes. IF you have messed with the exhaust system so that it makes more noise.
Noise is noise. Get used to it.

Otherwise, no absolutely not.

It did it from new with the stock can, is this normal? Sounds a bit like a rally car engine braking

 

[El Dorado]

:agree: Also if you have a cat delete along with a two brothers exhaust, a fuel map through Power Commander will help things.

I just went to the Power Commander website and they do not list Cam AM, any suggestions?

 

[Michaelscs]

When I am working down through the gears, or just slowing down, I get lots of popping, banging and misfires once I shut the throttle off, is this normal?

Yes, I would say it's normal on any F3 or F3s I've driven. I wouldn't call it banging or misfires, just popping on deceleration. I think it sounds good! I'm sure the Two Brothers greatly enhanced it.

 

[BajaRon]

It did it from new with the stock can, is this normal? Sounds a bit like a rally car engine braking

You may have been running lean on 1 or more cylinders from the factory. Each cylinder has its own injector. You may want to get that checked. Or, you may have had an exhaust leak early on. That can also add to the decel popping. But whatever it was (is) the 2 Bros exhaust will certainly exacerbate it, as mentioned above.

Other than blowing the guts out of your muffler, running too lean can create other problems as well.

 

[SpyderNeil]

It was doing it before the TB exhaust was fitted, it has been doing it since new. It's just much louder now

My F3T sot of burbles and pops on deceleration, as does my RT. The F3T is a bit louder, but they both do it. All modern engines run on the lean side to maximize fuel economy and since bike exhaust is closer to you, and a bit louder, it's noticeable.

Neil

 

[fatboy]

p c

power commander v

 

[Easy Rider]

It did it from new with the stock can, is this normal? Sounds a bit like a rally car engine braking

I don't know; I don't have your model.

I DID test ride my RT with a "performance" muffler on it and noticed none of that.

You REALLY should have addressed this BEFORE you made any modifications.

The dealer might ask that you put it back stock before they will look at it.

 

[Spyd_Piper]

When I am working down through the gears, or just slowing down, I get lots of popping, banging and misfires once I shut the throttle off, is this normal?

It is not normal. Backfiring in exhaust is 95% of the time an exhaust leak. In which fish air is pulled in under vacuum.
The other 5% of the time is tuning. A loud pop is lean at closed throttle position. Several small pops are rich from left over fuel and would be rich at the throttle position you just backed out of.

However, in your case, its not tuning. You can wrongly throw more fuel at it with a power commander to kill any chance of ignition. But its better to fix cause not the effect. You do not need fuel tuning. You need to find you leak. At all joints and gaskets at heads. Using a piece of 3/4-1 inch hose with 1 end at your ear and other end to probe around a running engine will find it easy enough.

Since your exhaust was probably put on for a performance gain rather than noise, we can remap your ecu to both change fuel and put down maximum power.

 

[Black Pig]

It is not normal. Backfiring in exhaust is 95% of the time an exhaust leak. In which fish air is pulled in under vacuum.
The other 5% of the time is tuning. A loud pop is lean at closed throttle position. Several small pops are rich from left over fuel and would be rich at the throttle position you just backed out of.

However, in your case, its not tuning. You can wrongly throw more fuel at it with a power commander to kill any chance of ignition. But its better to fix cause not the effect. You do not need fuel tuning. You need to find you leak. At all joints and gaskets at heads. Using a piece of 3/4-1 inch hose with 1 end at your ear and other end to probe around a running engine will find it easy enough.

Since your exhaust was probably put on for a performance gain rather than noise, we can remap your ecu to both change fuel and put down maximum power.

Okay, thanks for that. There is the answer to my question, it sounds like it is overfuelling. I very much doubt that both the original and the replacement exhaust both leak, the bike is only 3 months old and it has been doing it since day 1 with the original exhaust.

Can any bike dealer adjust this for me or do I need to go to the AD, the AD is 250 miles away!

 

[Spyd_Piper]

Okay, thanks for that. There is the answer to my question, it sounds like it is overfuelling. I very much doubt that both the original and the replacement exhaust both leak, the bike is only 3 months old and it has been doing it since day 1 with the original exhaust.

Can any bike dealer adjust this for me or do I need to go to the AD, the AD is 250 miles away!

That actually says that it is more of a leak. Right from day 1. Either at the head or a joint . Both places are up from where you put the exhaust on.

 

[Easy Rider]

Can any bike dealer adjust this for me or do I need to go to the AD, the AD is 250 miles away!

NOBODY can "adjust" it for you. With computer controlled systems, there is NO adjustment.
That is why people have been talking about an add-on fuel processor.

You REALLY should have checked this with a dealer BEFORE you started changing stuff.

There may be a defect somewhere ........but from the comments here so far, probably not.
And the only "fix" probably is to sink even more money into another mod to fix the first mod.

 

[Black Pig]

NOBODY can "adjust" it for you. With computer controlled systems, there is NO adjustment.
That is why people have been talking about an add-on fuel processor.

You REALLY should have checked this with a dealer BEFORE you started changing stuff.

There may be a defect somewhere ........but from the comments here so far, probably not.
And the only "fix" probably is to sink even more money into another mod to fix the first mod.

Well if the dealer was less than 4.5 hours away I would have been there, I have spoken to him and he assures me this is normal (with the original can) - Hmmmmm.