Backfire and popping.

[Big Tex]

This is the plug that I just changed out.

So this is my first Big Dog and I haven't really ever owned or rode anything but dirt bikes and crotch rockets... Yes I know sac religious!!

But anyways. I don't know anyone with a BD but when you guys are decelerating and down shifting do you get popping. I think it's normal with the Vance and Hines exhaust but not sure. It also was backfiring one loud pop when you start it cold or hot. I've changed the spark plugs and it hasn't backfired at start but still the loud popping on deceleration. Thoughts?

 

[BWG56]

check for air leaks around carb gaskets with a spray, and popping is usually a lean condition.

 

[Big Tex]

Check your jetting, I'm running .78 main and .31 intermediate and get a nice brown/tanish burning spark plug, also go thru carb adjustment it's pretty easy just google s&s carb adjustment, your running lean by the looks of the plug and that's why it's decel popping

Thanks for the info. I'll check into it.


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[Big Tex]

Check your jetting, I'm running .78 main and .31 intermediate and get a nice brown/tanish burning spark plug, also go thru carb adjustment it's pretty easy just google s&s carb adjustment, your running lean by the looks of the plug and that's why it's decel popping

Thanks for the info I'll check into it.


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[pknowles]

Thanks for the info I'll check into it.


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Not to high-jack your thread Tex but I just noticed you dog in the avatar seems to have a case of the ass.

 

[Mr. Wright]

Not to high-jack your thread Tex but I just noticed you dog in the avatar seems to have a case of the ass.

Dog? I thought it was a bear.

 

[HMAN]

S&S carbs when properly tuned will exhibit popping on decel. Nature of the beast. You can fatten up the settings and eliminate most pop.

 

[Big Tex]

Not to high-jack your thread Tex but I just noticed you dog in the avatar seems to have a case of the ass.

Why yes.. Yes it does! Haha. I was waiting to see when somebody would notice.



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[Twisted]

Why yes.. Yes it does! Haha. I was waiting to see when somebody would notice.



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Looks like one happy dog! I have the same thing as you, deceleration pop and a pop on startup most of the time, plus my plugs look very similar . I just pulled the carb and found it still has stock jetting even though it has the V&H piped, K&N filter and the restrictor plates opened up. So I just got a bunch of jets from J&P and plan on doing some testing hopefully this weekend. The decel pop was real bad with no baffles so I cut down the baffles and re welded them back together to make them shorter. Still loud but much better on the decel pop.

 

[BWG56]

Looks like one happy dog! I have the same thing as you, deceleration pop and a pop on startup most of the time, plus my plugs look very similar . I just pulled the carb and found it still has stock jetting even though it has the V&H piped, K&N filter and the restrictor plates opened up. So I just got a bunch of jets from J&P and plan on doing some testing hopefully this weekend. The decel pop was real bad with no baffles so I cut down the baffles and re welded them back together to make them shorter. Still loud but much better on the decel pop.

You prolly wanna start out with 31 and 76/78 first and see how it does after you warm it up and readjust the carb

 

[Twisted]

You prolly wanna start out with 31 and 76/78 first and see how it does after you warm it up and readjust the carb

Sounds like a plan, man! How about the air bleed leave it be to start or toss a 50 in there?

 

[BWG56]

Sounds like a plan, man! How about the air bleed leave it be to start or toss a 50 in there?

The 50 is a good size for the air bleed, I didn't have that jet so I just drilled mine out to .052, that was my closest bit