| Author | Message | ||
     Electraglider_1997 |
I wasn't convinced that mine was working so I took the Buell fake tank cover off and took it for a long ride yesterday to try to see the valve being pulled open by the cable. The dealer actually put their 2007 XB12S on their dyno to see how and when that cable actuated and then here's what they told me of their findings. It would only open under heavy load conditions and only at about 2500 rpms (and then shut) and then again at around 6000 rpms. Anyway, I got mine to open and shut a couple of times yesterday. It may have happened more than that but you have to realize that looking down at that mechanism on the airbox is not the safest thing to do while you are rapping out the engine and going at a high rate of acceleration. I only saw it open those couple of times at the high rpm and never at the 2500 rpm range. It seems to work though but I rarely beat the engine so I figure it probably only opens up only now and then. The only way to see this happening is to ride with that cover off and with the extra holes I've got in the airbox cover it is very intake honk loud compared to when the outside fake tank cover is installed. | ||
| Electraglider_1997 |
For those that might try to tell me that you can check it without running the engine by using the kill switch I say that only proves that it will open for that condition and that it doesn't get stuck open and nothing else. Now I know that mine opens, at least at high rpm. Another opinion of mine is that it is a little bit of complexity overkill if you ask me. I'd of rather they put that engineering into having oxygen sniffers on each exhaust pipe for better fuel injection control. Just my 2 cents. (Message edited by electraglider_1997 on October 30, 2006) (Message edited by electraglider_1997 on October 30, 2006) | ||
| Teeps |
My 2cents on the subject is the interactive exhaust valve/system is there only for noise abatement. Wire it open, then ride the bike and see what difference it makes, other than sound. | ||
| Lovehamr |
I like my race kit muffler. No voo doo valve!  | ||
| Electraglider_1997 |
Does anybody know what happens to the HP/Tq curves and values if the valve is wired open all the time??? | ||
| Teeps |
I wired the valve open on my bike before I did my own pipe mod. Other than the bark, I couldn't feel a nickel's worth of difference. But in the world of the butt dyno calibration, and results differers greatly. | ||
| Electraglider_1997 |
When I put Screaming Eagle mufflers on my Electraglide the gas mileage went from around 40 mpg way up to about 50 mpg. I assumed that it was due to the freer breathing provided by less restrictive exhaust release. I couldn't take the noise though so I put back on the stock muffs and opened them up with a long pointed rod and this helped and wasn't near as loud as the Screamin Eagles. Here's the question for those that have wired their valve open: Did MPG change so you could notice it??? Also, since opening up the airbox cover required an ECM recalibration, wouldn't opening up the muffler need some kind of reflash?? | ||
| Anonymous |
The XB interactive muffler is totally acoustically tuned, so there are virtually no gains to be had by changing the valve. In short, there are no "plugged up" diameters. The back pressure is virtually zero. The reason this works is because the muffer is big enough to fit in a number of acoustically tuned chambers. When you have small "stylish" mufflers like H-D, the only recourse is to choke the air path down. That's why you gain power and mileage when you open up their mufflers. | ||
| Jmhinkle |
So what you are saying is that the valve is strictly for sound and has no affect on the power curve? | ||
| Fastfxrs |
Anyone have any sound files of a stock pipe with valve wired open? Just curious. | ||
| Teeps |
Anonymous Posted on Tuesday The XB interactive muffler is totally acoustically tuned, so there are virtually no gains to be had by changing the valve. In short, there are no "plugged up" diameters. The back pressure is virtually zero. I cannot prove or disprove the above statement. But I am familiar with the design and manufacturing of mass produced automobiles. I can say for certain from a design and manufacturing point. No superfluous systems, parts or assembly procedures make it to final production. In other words, if it's not 100% needed, it gets left off... So by my, experience and logic(?), I have to wonder not what Mr Anonymous has said, but by what he has left unsaid. | ||
| Red_chili |
It would seem that he could NOT say that gains cannot be had by aftermarket mufflers - which dynos demonstrate. I believe what he is saying is, don't bother wiring the valve open because it causes no power loss in the stock can. In other words, it does not work by restriction, but by noise cancellation. | ||
| Electraglider_1997 |
Anonymous, Now that is the type of info I appreciate. Tanks hu eva u is. | ||
| Blake |
"So what you are saying is that the valve is strictly for sound and has no affect on the power curve?" No. What he is saying is that the Buell muffler is large enough to house two complete free flowing exhaust tracts, each tailored to provide optimum performance for its respective rev range. | ||
| Roc |
The interactive exhaust motors can begin functioning intermittently, if this happens it should be replaced because it is failing. | ||
| Electraglider_1997 |
Can anyone explain to me when the interactive exhaust valve is supposed to open and close? The more you folk write the more I am confused. If you are sitting in your driveway and in neutral and just rev the engine from idle to redline is that valve supposed to open? What does Anonymous have to say? | ||
| Scooter808484 |
It would seem that he could NOT say that gains cannot be had by aftermarket mufflers - which dynos demonstrate. I believe what he is saying is, don't bother wiring the valve open because it causes no power loss in the stock can. In other words, it does not work by restriction, but by noise cancellation. Hate putting words into someones mouth, but here goes anyway... Sure you can get better performance with aftermarket mufflers, but on every one of those it will say, "Not legal for street use." The stock can has to meet EPA noise regs, and the other ones don't. I don't think acoustically tuned refers to noise cancellation, but the fact that the valve changes the effective exhaust length, which in turn causes the exhaust to "tune" in at a different rpm. All has to do with pressure pulses and the timing of those pulses either helping or hurting the scavenging effect of the exhaust at a particular rpm. Longer length better for low rpm, shorter length better for high rpm. Service manual show how it works. With valve closed the gases appear to make two passes through the can, valve open short circuits and it makes only one. I don't know what the cam specs are for these bikes, but you generally need a little overlap to really get this to work well... more time when exhaust and intake are open together. Of course that means there's a better chance that unburned HCs can get out the exhaust and the EPA doesn't like that either. | ||
| Scooter808484 |
Electrglider, I think I read in the SM that it opens at low rpm WOT conditions to allow the motor to "spin up" faster. This is probably a back pressure reduction. Then it is supposed to open again at high rpm to get the can to tune in at that higher rpm. I'm sure there are throttle position restraints in the program though, so it might not do it in the driveway. If you did a full throttle pull to redline it ought to open somewhere though!! | ||
| Electraglider_1997 |
I think most people would be suprised if they took off the cover like I did and then went out and tried to get it to work. Mine only would open sometimes under screaming the motor to redline condition. Maybe mine has a problem but I think that most of you assume that testing it with the kill switch proves that it works and to me that proves nothing. I'd like to hear from Anonymous about how this thing is supposed to work. Guessing doesn't satisfy my need to know the facts. (Message edited by electraglider_1997 on November 01, 2006) | ||
| Jmhinkle |
Just to satisfy my own curiosity on some things, what is the safest way to wire it open without screwing up the servo motor that will still want to run? | ||
| Debueller |
When I installed my Drummer (which does not have the valve) I disconnected the cable from the servo motor and zip-tied it aside. On the muffler end I zip-tied it aside, I think to another wire harness. By leaving the cable in place, it would be easy to re-connect everything if needed someday. To keep dirt out of the unused cable and to make for a cleaner looking install, I used heat shrink wrap on each end of the cable to seal it off. This method will allow the servo to operate, "tricking" the ECM into thinking the everything is orignal and stock. | ||
| Treadmarks |
To wire the valve open at the servo, I used a rigid piece of plastic tubing that I had split on one side. I disconnected the cable at the servo, pulled it open all the way, and slid the tubing over the wire part of the cable. I also use a few small wire ties on the ends of the tubing to prevent it from opening. With the race ecm and the stock exhaust, and with the servo connected I had tons of bottom end torque, but the motor did not rev up as well on top end. With the servo cable secured in the open position, I did not have much bottom end and the motor sort of stumbled on acceleration, but once you got the rpms up over 4000 it would pull like crazy. The system does indeed work very well as designed just not loud enough to make other drivers aware. | ||
| Thunderbox |
I think anonymous is probably correct. I installed a Drummer early on and I had a dyno done prior to and after installation. The gain in HP was not very impressive. 2 HP at high RPM. Torque fell off at lower RPMS and peaked at exactly the same as stock but at a different RPM. The muffler was very noisy and I took it off and sold it after only 7 days. I was sure it had better grunt but the dyno test proved otherwise. It sounded faster for sure but it wasn't at all benificial. I think we should listen to anonymous, he knows something we don't. | ||
| Scooter808484 |
I think anonymous is probably correct. I installed a Drummer early on and I had a dyno done prior to and after installation. The gain in HP was not very impressive. 2 HP at high RPM. Torque fell off at lower RPMS and peaked at exactly the same as stock but at a different RPM The muffler shootout report on American Sportbikes website shows that the Drummer can have significant torque benefit in the midrange, it if is tuned properly! Changing the exhaust can have a really huge impact on airflow through the engine, not just at WOT but at all throttle settings and rpms. The FI has no idea of how much air is flowing, other than what the initial program tells it. Those tuned pulses make a really big difference. That's why the valve helps, it changes the frequency response of the muffler so that it can be closer to optimum at two rpm ranges, instead of just one. I don't have any specific knowledge of the Drummer, but my guess is that it's tuned to boost midrange torque and that it can produce the same top end, without the valve, because there is less flow restriction, since it is not meeting any EPA noise regulations. AFAIK, the Drummer is designed to tune up OK with the stock ECM, better with the Race ECM. | ||
| Thunderbox |
Significant gains in HP if it's tuned properly you say. Therein lies the big problem. Finding a place that can properly tune an engine to the exhaust. It's just too much hit and miss. I was told the Drummer would make a noticeable improvement just bolting it on. Didn't happen. Sounded like it did but the truth be known the Drummer was just too dang noisy for me. If you cracked a stock Uly muffler open you would probably be very surprised what it looks like in there. Not to much of anything really. I think this is an area that Buell has really done there homework. | ||
| Scooter808484 |
Thunderbox, No question that finding someone to tune one is a huge problem. I've been working on my Delphi FI Road King for four years now. There's no one anywhere near here that I would trust to tune it, so I bought an O2 sensor and hacked at it myself, using the long black dyno. I can do a decent job of setting AFR, but I don't have anything to measure closely enough to set timing very accurately. The guys that I know about that do a good job would charge about $400, and if you ever did it yourself, you'd know that to be a bargain!! | ||
| Red_chili |
Um, downloading one of Al Lighton's maps doesn't seem too insurmountable... | ||
| Thunderbox |
No it's not but you are exactly where you were before that if it isn't perfect. So I have decided that A. I like my Uly Quiet and B. I did a cross Canada run 2 up and didn't need more power. So I am going to leave the machine the way Erik made it. Most will say they love the bike and the engine is great but most want something that wasn't supplied originally with the bike. I am just too happy with it. | ||
| Red_chili |
Fair 'nuff. I just have this visceral need to drown out my fan, ex-specially at idle...  That, and dealing with 20% less air up here has my hooligan needs only 80% met. |
