XB12 Muffler Valve Setting

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cterry66

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Joined
Aug 28, 2020
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For those that have ECM Droid or other Tuning Apps, what is the prefered ECM setting for the Automatic muffler valve?
My stock Map had the valve programmed to open on Wide Open Throttle. A Map I just got From Revision for the stock XB12 Muffler also had the same setting and they told me that map was actually an EBR Map. Other settings options are, turned completely off, or turned on the open and close throughout the Rev range.
 
This is a shake your head question...
If you want your bike to run to epa specs leave it be.
I used to turn them off and wire the valve open. Some people just removed the cable and wired the valve open.
The reason why it’s a epa the xb12 made more noise and the exhaust valve was the fix.
The reason I turn it off and wire it open is because it’s a poor design road debris coats the cable, cable fails.. unless you constantly clean and maintain it.
 
cterry66, was recently trying to understand why the stock tune with a stock muffler was performing so poorly?
The very last sentence of the ECMSPY Guide for the "Exhaust Valve Settings" says:
"With the control voltage reversed, which is the default setup, the exhaust valve opens at the first switching point, closes at the second one and will be opened at the third RPM threshold."
This setting works as described on my 2009 XB12X Uly with a working AMC, and I went from ~33mpg to about ~43mpg and runs way better.
The other exhaust settings from different sources seem to have the exhaust valve working the opposite direction?
http://www.ecmspy.com/ug_mono/V2.0/system.shtml#exhaust-valve
These Exhaust settings are accessible in ECMDroid, I had no problems making this change, but was cautioned by other sources that ECMDroid/ECMSPY voids my products warranty.
 
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I should start answering those robocalls! "Yes, I would like a aftermarket warranty on my 12 year old motorcycle!, Please tell me more!"

Theres something wrong with your tune. IEV action alone cannot affect the average mpg by 10, and 33mpg is crazy rich! Besides, any halfway decent ECM tune will do it's job and lean it out to stoic at cruise where it should be, regardless of IEV action. If you are at WOT that often, it explains the MPG, LOL! Forcing it to run a rich CL target (or a OL tune) at cruise is wasteful and completely pointless. Adding fuel at steady part throttle cruise has no reasoning unless you like changing fouled plugs, and rolling coal on a Buell is silly.

The IEV adds a little back pressure to increase mid-range torque in a stock muffler and even out the 3500-4500 dip in the curve that Buells have without it. Wiring the valve open or leaving it closed both reduce the amount of power the engine makes throughout the RPM sweep. Assuming the affects of this change without any data points is not going to be an affective tuning solution for anyone.

IMO, for a street bike, leave all the CL and targets alone, because thats where you ride it. You could mess with OL tuning on a dyno at WOT only if you want to see those extra 5 hp that are there. Or download the FREE Buell race tune and be within 99.84536876% of perfect in 10 minutes flat.
 
The Ferrari LaFerrari uses variable intake runner length for the same purpose, and Engine Masters has done exhaust primary length testing before. Their last episode was on individual intake runner length, but you gotta have Motortrend to see it.
 
The IEV adds a little back pressure to increase mid-range torque in a stock muffler and even out the 3500-4500 dip in the curve that Buells have without it. Wiring the valve open or leaving it closed both reduce the amount of power the engine makes throughout the RPM sweep. Assuming the affects of this change without any data points is not going to be an affective tuning solution for anyone.

Thanks Cooter. Is there any known issues with using Buelltooth and ECMDroid/ECMSPY to make exhaust valve changes as shown in the ECMSpy Userguide? These are the changes I have made to a stock ECM that came with the Uly, and another ECM that I purchased with a tune.
The results have been the same on both ECM's, and perform the way you describe it, which is good.
 
The Ferrari LaFerrari uses variable intake runner length for the same purpose, and Engine Masters has done exhaust primary length testing before. Their last episode was on individual intake runner length, but you gotta have Motortrend to see it.




But no cup holder for your beer, so what do you care. Epic "CoOterfail (tm)"


We really need to get you to host an episode of VinWiki.
 
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T-bone: The only issues I see is making changes without a dependable test regimen to see if those changes are helping or hurting you. The operation of the valve will simply do what you tell it to, regardless whether it's killing power or not, but won't cause you "issues".
IMO, if you want proven power and dependable operation, use the proven recipe. OE race tune, open airbox, delete the IEV, and go aftermarket muffler. There are quiet ones and there is a race tune version for the stock muffler as well. You will work very very hard to walk the long path to get close to those OE race tune gains by yourself. But... if fiddling is your thing, have fun man. For some it's the destination, for others, its the journey.

Careful what you ask for Thirty-four:19! BITD, I spilled a little Miller Genuine Draft while sitting in a Lamborghini with a frisky redheaded GF that I named Larry. Maybe some DNA too:eek:. A purple Lambo S, with big chrome wheels, that was "lowered" by someone screwing the coilovers to the stops. Classy, right? I actually ended up changing the clutch in that car, all from the bottom, with no lift, 4 months and almost $20,000!!! No wonder my back hurts today.
 
Careful what you ask for Thirty-four:19! BITD, I spilled a little Miller Genuine Draft while sitting in a Lamborghini with a frisky redheaded GF that I named Larry. Maybe some DNA too:eek:. A purple Lambo S, with big chrome wheels, that was "lowered" by someone screwing the coilovers to the stops. Classy, right? I actually ended up changing the clutch in that car, all from the bottom, with no lift, 4 months and almost $20,000!!! No wonder my back hurts today.

Sounds like you had a date with Kimmie.



TL;DR - https://www.facebook.com/XtremeXperience/videos/2971333059591332/
 
Make no mistake, I didn't own the car, and I don't have butt implants:black_eyed:, and ya Outlaw I called her "Larry" as in absolutely, massively, no meds can help her, bat****, 10 flew over her cuckoos nest. And all the 'benefits' that come with that:love-struck: Sometimes I wonder where she is, but then think of her probable body count by now, and immediately fear that she knows where I live:eek-new:
 
and you got so much more!... LOL. Aren't you glad you asked;) njloco was right in post #2. The valve is open most of the time (including WOT), and only closes in that torque dip area of 3500-4500 RPM. Thats why you can't really see whats going on with a neutral rev. You'd need a dyno and steady state RPM test. If you can activate it in active tests, I'd be OK assuming it's working at RPM.

with a frisky redheaded GF that I named Larry.

I'm a Godly man and try to never ever use the Lords' name in vain....but Christ Almighty.

It's an experience one can only do as a young man:anonymous:
 


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