Decel popping

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yukonerdave

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Bike is running strong and sounds great with the HMF full exhaust. When it gets hot I get significant popping from both pipes when decelerating. A quick poke around suggests that this is not uncommon when you change exhausts, and that it results from too lean a mixture. Does that sound right? I have the pilot screws set at 2 1/4 turns out all around. To richen the mixture do I turn them in or out? Should I do the same thing to all of them, or play around with each screw at a time? It isn't terrible as it is, but the popping is just annoying enough to make me want to attempt to eliminate it. Thanks!
 
I think a pop on decel only could be an exhaust leak...

I fixed my decel pop a year ago with a re-install with RTV sealent.
This year, I got another exhaust leak as we tried swapping a differwnt muffle.
Yanked the pipes to the point they leaked.
 
Turning out (counter-clockwise) richens. I have mine at 3&1/4 turns out. Runs good--no more popping.
 
Hey Dave
I set them at 2.5 turns when I sent them to you so with a new pipe you will have to open them up to get rid of the popping. Like already mentioned check for exhaust leaks as well.
Let me know if you need any after "donation" service. More than happy to help
Cheers
 
Do you folks know a good way to check for exhaust leaks?

Thanks.

Elimax
 
Some say you can hear it, but I can't. I would look for soot around the heads/pipes, which would indicate a leak.
 
Bike is running strong and sounds great with the HMF full exhaust. When it gets hot I get significant popping from both pipes when decelerating. A quick poke around suggests that this is not uncommon when you change exhausts, and that it results from too lean a mixture. Does that sound right? I have the pilot screws set at 2 1/4 turns out all around. To richen the mixture do I turn them in or out? Should I do the same thing to all of them, or play around with each screw at a time? It isn't terrible as it is, but the popping is just annoying enough to make me want to attempt to eliminate it. Thanks!

as others have said, ensure no exhaust leak, if so def richen it up a bit. i would try setting each 1/4 more out at a time and go from there. i had mine set with a sniffer, and they were between 3 and 6.5 turns out.

I think a pop on decel only could be an exhaust leak...

not try, def could be lean a/f screws...

Do you folks know a good way to check for exhaust leaks?

Thanks.

Elimax

should be able to put your hands around the headers and if you feel any air u have a leak. i have a tiny one on one of my headers but its not causing any problems.
 
Backed all 4 out a quarter turn and it made it considerably worse. What does that mean? Should I try backing out further, or turn em in further than before? What happens when the mixture is too rich?
 
Backed all 4 out a quarter turn and it made it considerably worse. What does that mean? Should I try backing out further, or turn em in further than before? What happens when the mixture is too rich?

it will feel 'bogged down' but not 'stumbly' like lean will...

backing them out should NOT have hurt this if it was a lean condition. ok, heres a question...

run your bike with like half choke, does that help it? if not, then i'd start looking @ exhaust leaks.
 

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