| Author | Message | ||
     Manimal |
Ok, so i've noticed that my exhaust makes a popping noise when i downshift or when i pull the clutch, like when approaching a stoplight. I'm running a D&D exhaust w/ Heat wrapped headers, K&N air filter and a race ECM. It has been popping for a while but it seemed to be more consistant today. Normal or should i start to worry? Anyone out there with a similar setup experience this? Thanks buellers!!!! | ||
| Badlionsfan |
check your connections on your muffler. popping is caused by unspent fuel being ignited in the exhaust system. for ignition to occur, there must be oxygen. oxygen get's in by low back pressure and leaks. since you say it's gettin worse, the latter could be possible. if all is tight, someone else will have to chime in cuz i don't know. i have heard people say that some popping is normal tho. | ||
| Ft_bstrd |
Try here: http://www.badweatherbikers.com/cgibin/discus/sear ch.cgi | ||
| Manimal |
ok Ft bstrd, so i read your post about it equalizing the pressure. but is this bad. Did you do anything to setup to eliminate the popping noise? I think you have a close setup to mine? | ||
| Buelltroll |
It sucks and sounds like crap. But if you don't have an intake leak,It's normal unfortunatly. | ||
| Tom60 |
Pops´n crackles .. I LOVE it  Heck, even my car does that (with Stingers  ) If it is not caused by an excessively lean mixture /I once rode a friends Electra Glide that would pop like mad whenever you let of the gas - turned out he had a head gasket leak/ - then it doesnt do any harm, just the sign of borderline lean mixture and free flowing exhaust.. | ||
| Chadr81 |
I have the same setup as you, and mine does the same thing. Seems to do it more, when the bike is cold, for the first 10 min or so until the bike is really warmed up. Other Buellers bikes I know do the same thing. It's completely normal. Chad | ||
| Tom60 |
Yes: Cold air = more oxygen = leaner mix.. I can tweak it on my other (carbed) bike with idle mixture screw, when it is cold outside.. but I´m lazy to do it most of the time  | ||
| Ft_bstrd |
Manimal, I don't have an exhaust leak. I have sealed everything with RTV. I have the Race ECM so the mixture is as rich as you can get without custom programming the ECM or potentially fouling the plugs while cold. Under deceleration, it still pops. I notice it most when I am coming off of hard decel moving into slightly softer deceleration. So when the exhaust pressure is highest, it doesn't pop but does as the exhaust pressure begins to decrease. I think the leaner environment has a little to do with it, but IMHO it is a component of the nature of the power pulses of the engine. Because they are not regular but irregular, I believe there is a longer duration between power pulses than you would have with a parallel twin, 90*, 60*, etc. I believe that that longer "off pulse" allows cold outside air to rush in the outlet causing a pop. I believe that you do not experience this as much with the stock pipe because of the exhaust servo. It levelizes the pressure within the muffler to the extent that high and low pressures differences are reduced. I think you could adjust the fuel delivery so that it was so rich you would choke on gas fumes and it would still pop. I believe it a nature of the beast. I would be interested if there is anyone who has a similar set-up whose bike DOES NOT pop. I don't believe that anyone has stepped up so far with a solution without modification of the pipe. The best potential solution I have seen was in attaching a disk type spark arrestor to the outlet pipe.  I believe it would restrict both the exhaust leaving the pipe as well as air re-entering the pipe. These are all my opinions and are based on nothing but the ramblings of my sick mind. I'm sure there are dozens who can chime in and disprove my theories. | ||
| Tom60 |
How much fuel does the Race ECM add with throttle closed (compared to stock ECM) ? Adding fuel other than on idle would have no effect on popping.. | ||
| Odinbueller |
Usually the popping on decel with a free flowing exhaust & race ECM is a lean pop. I believe the map on both the stock & race ECM have a very low fuel value at high RPM and 0 throttle position. If you have a DirectLink, you can add some fuel at 0 throttle position from 1750 RPM up to redline, and it should alleviate most of it. I recommend the bike be tuned at a facility that knows Buell & DirectLink and not try to adjust anything on your own, as major problems may result. Also, you may not even get rid of all the popping using this procedure. You may still get the occasional pop here and there. Hope this helps, Chris | ||
| Tom60 |
In other words - it is ONLY the idle A/F ratio that counts IMHO ... I´m no expert on this  , but why look for complicated explanations, when I can turn the popping on and off at will - just by setting the air (idle) screw ? | ||
| Tom60 |
Chris- you beat me to it by a minute ! (Message edited by tom60 on August 11, 2007) | ||
| Tkxb9sx |
mine does it too. it does it right around 3500 down to 2500. give or take a few hundred. its only normal. you have a v twin. i do too. he he | ||
| Loose_cannon_1203cc |
That's how you know it's an american engine baby! I love the popping and cracking, makes a lot of heads turn! |
