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[PierceEye]

2010 Convertible 8200 miles in Tampa, FL. V&H Large Radius pipes, HD Heavy Breather, Dynoed in Sept. 2010 with 1800 miles on it.

About 3 weeks ago on a ride of 200 hard miles and a rain storm it heard it pop a few times on a hard deceleration but revs never over 4300

Now while it is at idle I am getting this pop.........pop pop....pop.................pop cycle. When I am cruising I can't hear it but that could be they are loud and the wind in the ears.

I tightened the exhaust and got 1/4 turn out 3 of them....checked all intake points and made sure they were tight

Ay ideas and should I not ride it in fear of burning a valve?

Thanks

Roger

[dlaws01]

Several things could possibly be causing your problem and you will have to start eliminating them from cheapest to the most expensive.  Although you have tightened the exhaust flange nuts, if the existing gasket on one port or the other has burned through, it will still be leaking and might be the cause.  Replacing both exhaust gaskets and giving the exhaust system a thorough inspection is probably where I would start first.  JMHO

[PierceEye]

Several things could possibly be causing your problem and you will have to start eliminating them from cheapest to the most expensive.  Although you have tightened the exhaust flange nuts, if the existing gasket on one port or the other has burned through, it will still be leaking and might be the cause.  Replacing both exhaust gaskets and giving the exhaust system a thorough inspection is probably where I would start first.  JMHO

Thanks

[BeeCVOBreakOut]

It may be your tune. I found this response to a post from someone asking basically the same question:

So, the popping you are hearing is not back-firing. It is a popping resonating sound generated by a lean condition on decel. When you suddenly close the throttle, the incoming air is choked off and the closed throttle also causes the bike to return to idle on the very lean idle circuit of the carb(s). However, momentum of the bike is actually "driving" the engine in a sense, and that engine is still spinning at rpm that needs far more gas than the closed throttle/carb can provide. The engine is still spinning but the incoming fuel rate is very low, until just enough builds up in the combustion chamber to "fire" on the exhaust stroke of the engine.

To know this for sure, the next time it happens, pull in the clutch and the popping will stop immediately, because the bike's momentum is not pushing the engine to spin. Don't "change the plugs" like some people suggest, its a waste of time and money. Messing with the ignition timing really won't help either, because it is still a lean fuel/air mix on decel that is the cause. Note, I said cause and not problem, because the popping is not at all damaging to the bike. So don't expect your dealer to fix the "problem" under warranty because it is not a warrantable situation. The EPA drove this more than anything else.

 

A recent update on this. Ever wonder why the stock mufflers on your bike are so big and heavy? Well, one reason is sound attenuation. Big mufflers provide a lot of volume for the rumbles and popping in the exhaust to be toned down by resonating in the larger muffler canister. Motorcycle builders also have to meet sound regulations along with emission standards. Some of that sound proofing is in the mufflers. But aftermarket mufflers, easier breathing, usually lighter and smaller, don't offer that same volume. Less volume, less sound attenuation = more noise and more popping. Again, don't complain to the dealer about this unless you plan to spend the money to correct the fuel/air mix ratio to make up for the increased airflow through the engine.

Modifying the exhaust (especially if it gets louder) will only make it worse, and louder when it pops. Because most aftermarket pipes produce "lower back pressure", it makes matters worse yet because lower back pressure pipes actually cause the fuel/air mix to LEAN OUT EVEN MORE. The solution is in the carbs, and it requires a richer fuel/air mixture. The only logical way to do that is spend about $300 to get a Dynojet or K&N brand "jet kit" installed. Do not mess with that carb jets yourself, do not mess with airbox, do not simply install a high flow air filter (which also can lean out the mixture) itself. If you want the bike to run a lot better and no pop on decel, spend the bucks on a jet-kit, you will be very happy with the results and it'll do a LOT more for performance than louder pipes ever will. In fact, I'd be willing to bet a jet-kitted bike with stock pipes would probably beat a stock carbed bike with aftermarket pipes.

[Buckeye_Tuning]

It may be your tune. I found this response to a post from someone asking basically the same question:

So, the popping you are hearing is not back-firing. It is a popping resonating sound generated by a lean condition on decel. When you suddenly close the throttle, the incoming air is choked off and the closed throttle also causes the bike to return to idle on the very lean idle circuit of the carb(s). However, momentum of the bike is actually "driving" the engine in a sense, and that engine is still spinning at rpm that needs far more gas than the closed throttle/carb can provide. The engine is still spinning but the incoming fuel rate is very low, until just enough builds up in the combustion chamber to "fire" on the exhaust stroke of the engine.

To know this for sure, the next time it happens, pull in the clutch and the popping will stop immediately, because the bike's momentum is not pushing the engine to spin. Don't "change the plugs" like some people suggest, its a waste of time and money. Messing with the ignition timing really won't help either, because it is still a lean fuel/air mix on decel that is the cause. Note, I said cause and not problem, because the popping is not at all damaging to the bike. So don't expect your dealer to fix the "problem" under warranty because it is not a warrantable situation. The EPA drove this more than anything else.

 

A recent update on this. Ever wonder why the stock mufflers on your bike are so big and heavy? Well, one reason is sound attenuation. Big mufflers provide a lot of volume for the rumbles and popping in the exhaust to be toned down by resonating in the larger muffler canister. Motorcycle builders also have to meet sound regulations along with emission standards. Some of that sound proofing is in the mufflers. But aftermarket mufflers, easier breathing, usually lighter and smaller, don't offer that same volume. Less volume, less sound attenuation = more noise and more popping. Again, don't complain to the dealer about this unless you plan to spend the money to correct the fuel/air mix ratio to make up for the increased airflow through the engine.

Modifying the exhaust (especially if it gets louder) will only make it worse, and louder when it pops. Because most aftermarket pipes produce "lower back pressure", it makes matters worse yet because lower back pressure pipes actually cause the fuel/air mix to LEAN OUT EVEN MORE. The solution is in the carbs, and it requires a richer fuel/air mixture. The only logical way to do that is spend about $300 to get a Dynojet or K&N brand "jet kit" installed. Do not mess with that carb jets yourself, do not mess with airbox, do not simply install a high flow air filter (which also can lean out the mixture) itself. If you want the bike to run a lot better and no pop on decel, spend the bucks on a jet-kit, you will be very happy with the results and it'll do a LOT more for performance than louder pipes ever will. In fact, I'd be willing to bet a jet-kitted bike with stock pipes would probably beat a stock carbed bike with aftermarket pipes.

And this has exactly WHAT do do with an EFI bike?

[dlaws01]

That is exactly why I didn't go into ALL the potential causes of your symptoms.  My reasoning was to start with the simplest solutions first and eliminate them then gradually move toward the more complex and labor intensive causes for the symptom.  Otherwise it's a crap shoot as to what is causing the problem and you will only be guessing at which one is the problem.  I've found in my experiences doing maintenance that it's best to start off with the simple solutions and don't read into the problem more than it is.  Keep it simple and work up from there.  Good rule to follow. JMHO

[PierceEye]

That is exactly why I didn't go into ALL the potential causes of your symptoms.  My reasoning was to start with the simplest solutions first and eliminate them then gradually move toward the more complex and labor intensive causes for the symptom.  Otherwise it's a crap shoot as to what is causing the problem and you will only be guessing at which one is the problem.  I've found in my experiences doing maintenance that it's best to start off with the simple solutions and don't read into the problem more than it is.  Keep it simple and work up from there.  Good rule to follow. JMHO

I agree dlaws01 might just take it to the dealer....I can do it (restoring a BSA now) I just don't have time let alone if it is not the exhaust I would take it in
But I do appreciate all the advice greatly.

Roger

[PierceEye]

Here I loaded this up on my You Tube

[FLTRI]

2010 Convertible 8200 miles in Tampa, FL. V&H Large Radius pipes, HD Heavy Breather, Dynoed in Sept. 2010 with 1800 miles on it.

About 3 weeks ago on a ride of 200 hard miles and a rain storm it heard it pop a few times on a hard deceleration but revs never over 4300

Now while it is at idle I am getting this pop.........pop pop....pop.................pop cycle. When I am cruising I can't hear it but that could be they are loud and the wind in the ears.

I tightened the exhaust and got 1/4 turn out 3 of them....checked all intake points and made sure they were tight

Ay ideas and should I not ride it in fear of burning a valve?

Thanks

Roger

Has the bike been tuned for those pipes?

If so, did the tuner leave the bike in closed loop after he was done?

Lots of closed loop issues can be caused by short pipes and the rear is short.

The bike will literally tune itself out of good running right into crappy running in under 100 miles.

Reload the calibration and the bike runs as good as the day it was tuned.

If so, change calibration to open loop under 50kpa for all rpms and again reload the calibration which also resets the AFV. If that fixes it your done, if not onto the next steps.
HTH,
Bob

[PierceEye]

Hi Bob,

Yes it was tuned with a SEPST when I had the piped and intake installed at 1300 miles in Sept. 2010
It has ran fine all those  miles unless I just did not hear this.

Is when I really noticed is I am getting ready to trade it in and the dealer asked to take a video as I just can't get to the dealer as I am busy right now. I normally fire the bike up as I am rolling it out of the cave and it never stuck out that clear until I fired it up and took a video in the cave.
Now it is possible it sounds worse than it is due to echoing inside the cave and I have that race Deck flooring which would make it pitch higher and louder I would think.

Many Thanks....I have the tuner in hand and am going to the dealer........going to try to seal the deal on the CVO Ultra 1st then if were not where we are I will put it in the shop and wait for the 2014's


Roger

[PierceEye]

So I fixed the problem.......cost me almost $15k though 

[PierceEye]

So I fixed the problem.......cost me almost $15k though 

[PierceEye]

[PierceEye]

[Fired00d]

So I fixed the problem.......cost me almost $15k though 

Wow... that's one way of fixing it ... but now you get to start all over w/the mods.

 
Ride Safe,
Fired00d