Jetting Question

thexaulted

Member
I have a jetting question, as I just got back from Daytona Beach, and was riding with some of my buddies that I don't ride with all of the time (I'm a NJ guy in SC now).

Ok, let me start with the fact that I have Joker pipes that are pretty short and the pipe to the rear head has considerably more bluing then the pipe to the front. When I come off of the gas there has always been a bunch of popping that at night shows up as small blue flames coming out of the pipes. I've always considered this as normal for the bike and the mechanics that have worked on it have never mentioned it as being a problem. I know they haven't ridden it at night but I'm sure they can hear it.

Well my buddies (and some other guy I didn't even know) kept telling me the bike is running too rich and the unburned gas when coming off the throttle is the flames and that if I don't do something about it, re-jet, I was going to cause some kind of damage! The plugs seem good whenever I check them, in as far as there's not fowling.

I would appreciate any advice if from someone that is more knowledgeable on the subject!! Thanks, Rich
 

Ratman

Active Member
Mine was popping on decel (V&H BR 2-2) and Raywood advised me to check exhaust flanges/studs for possible leak. I tightened the flanges slightly and that took care of the problem. Put a second set of nuts (to act as lock nuts) on the exhaust bolts. Just a thought. Good luck!
 

thexaulted

Member
Mine was popping on decel (V&H BR 2-2) and Raywood advised me to check exhaust flanges/studs for possible leak. I tightened the flanges slightly and that took care of the problem. Put a second set of nuts (to act as lock nuts) on the exhaust bolts. Just a thought. Good luck!
Thanks Ratman I'll give it a try!
 

lee

Well-Known Member
popping out the exhaust would generally be an indicating of a lean condition, rather than rich. An exhaust leak could definitely be the problem but it might be fine. Some pipes have that characteristic more than others. You would also have to be running rich to the extent that gas would wash the oil from the cylinder walls to really do any damage and your plugs would probably be black. Mine popped on decel more after a dyno tune so you might be worrying about nothing
 

thexaulted

Member
Thanks Lee, that's why I wanted to hear from some BD brothers on the subject, I don't want to be worrying for nothing but I'm not in the know so these guys set me off worrying about it and I like to do things right!
 

BadBrad

2005 Pitbull
Mine and my wife's both pop a little on decel. Generally, pipes without baffles tend to do this more than a pipe with a full baffle. I actually like a little pop on decel.
 

thexaulted

Member
OK as far as the plugs go, the front plug is blackish and the rear plug is greyish and the rear one is the one that seems to be hotter as the pipe has a lot more bluing. As far as stock besides the pipe, I have the wire plus set up and a dyna 2000 ignition but no motor work.
 

Brew

Troop Supporter
Do you know the size jets you're running? By the way you just mentioned, it sounds like you may be running a tad bit lean...
 
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RRRUFF

Well-Known Member
Like said above check for exhause leaks. If you don't find any then go up a jet size. Jets are cheap. Lean = decel pop. From what you said about the color of the plugs you maybe a little lean. However with those pipes you are likely to always have some decel pop, the plugs are the best indicator.
 

thexaulted

Member
Checked for exhaust leaks and couldn't find anything too obvious, bolts at flanges were all tight, I was only able to tighten one slightly.
As far as the jets are concerned I don't know what size I am running but would I only need to change the main? You guys think lean though, not rich?
 

Brew

Troop Supporter
Well it's kind of hard to tell what happend to the scoot. When the pipes are put on and a different air filter is used then usually we re-jet to compensate. Best thing to do is find out what size jets you are running since you have no exhaust leaks. I think that would help us with getting you a better answer. However, it sounds like your scoot is running fine to me...:2thumbs: The only concern I would have is if the scoots running hot, then you should take action...Just my opinion!
 
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thexaulted

Member
Thanks I am going to try this readjusting procedure before I pull the jets. I also went to the S&S website and in their quick tuning steps it talks about sneezing indicating a lean condition. I have had what I have been calling an intermittent hiccup for a while, I guess you could call it a slight sneeze, so maybe the intermediate is to lean.

Why would the front plug seem rich and rear lean though?
 

RRRUFF

Well-Known Member
Thanks I am going to try this readjusting procedure before I pull the jets. I also went to the S&S website and in their quick tuning steps it talks about sneezing indicating a lean condition. I have had what I have been calling an intermittent hiccup for a while, I guess you could call it a slight sneeze, so maybe the intermediate is to lean.

Why would the front plug seem rich and rear lean though?
If your accelerator pump actuator isn't adjusted properly it could cause this hiccup also when you roll the throttle quickly.
 

knucklehead

Member
You may have an intake manifold gasket leak. Try spraying some carb cleaner at the intake manifold gaskets while the motor is running and see if the idle changes.
 

thexaulted

Member
You may have an intake manifold gasket leak. Try spraying some carb cleaner at the intake manifold gaskets while the motor is running and see if the idle changes.
Could an intake manifold gasket leak cause the difference in the plugs, one being leaner? I will check that tomorrow tomorrow also!
 
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