| Author | Message | ||
     Conchop |
Whilst installing Odies heat blanket on my 08, I noticed the cable for the muffler valve was very loose on the pulley. Low and behold, there was an adjuster on down that cable. So I adjusted it like I would any motorcycle cable - not tight as a banjo string - just a wee bit of slop. This seems to have changed things a bit. Low end power and throttle response seems to have improved. There also seems to be an immediate throttle body honk with a smoother and more linear delivery of power. The idle seems quieter, too. QUESTION - Am I imagining the extra low end power and lower vibes or is my ass dyno on drugs. Anyone else try this??? imabigolhappyboy. | ||
| Electraglider_1997 |
You really have to get on it hard to even get that valve to cycle open so unless you are really WOT it doesn't much do anything. I've watched it work with the fake tank cover off. | ||
| Natexlh1000 |
So if there's extra slack in the cable, does that valve open or close, or does it just flop around all over the place? | ||
| Ratbuell |
The valve is spring loaded, but I forget which way; it won't flop, it just won't work right. Loose cable = less valve travel. | ||
| Longdog_cymru |
It is spring loaded to close as a default. | ||
| Conchop |
Its a Uly - so WOT seems to be SOP. LOL,nonetheless, something is different. | ||
| Blake |
Don, Thanks for sharing your discovery. I'm thinking that all affected XB12 owners should be checking/adjusting their muffler valve actuator cable. Hope you don't mind that I changed your thread title. I suspect that a number of folks would have otherwise missed this excellent information, so I changed "I seem to have found some more ass" to the current title. Thanks again for taking time to share your discovery. It's the first I've heard of that. | ||
| Blake |
What is "SOP"? | ||
| Ry329 |
Standard Operating Procedure.............. | ||
| Ry329 |
Or Practice.. | ||
| Bobr |
Very interesting. I wonder what effect ad justing the cable has on the valve and actuator. I've heard that the cable can be related to some problems with the actuator/valve resulting in the CEL signalling a trouble code. I also wonder if adjusting the cable affects when the valve opens, and if that in turn could affect performance and/or fueling. | ||
| Blake |
Probably not "when", but surely "how far". | ||
| Jlnance |
There is a procedure for checking the operation of the valve. I believe it is: 1 - key off 2 - kill switch running 3 - wide open throttle 4 - key on This will cause the valve to cycle. I found that if my cable is too tight, the actuator is not powerful enough to pull it. You all might want to check this when adjusting your valve. | ||
| Natexlh1000 |
My friend and I were talking about manually tweaking the valve with a handlebar control. Then we stopped talking about it and went riding instead  | ||
| Conchop |
OK - Here's the deal - After reading some of your comments, I peeled the tank cover off and started experimenting. Apparently the cable PUSHES the valve open. Weird as hell. While idling, the cable below the adjuster was pushing the valve open just a bit. The quiet idling I reported earlier was because tightening the cable actually closed the valve. Weird as hell, too. Must be how the cable housing butts up. If you hear a jingling sound while your bike is idling, chances are your valve is opened when it shouldn't be. That is what is making the jingling sound. Now it sounds like a lawn tractor at idle. There is something to be said for back pressure. Too quiet BUT - the lower vibrations and the extra power at lower rpm's has increased the overall drivability. I can now comfortably dip into the 2k rpm range and pull out smoothly. Way more satisfaction. | ||
| Conchop |
PS - odies blanket works real well - but you have to lay it flat across the frame rails to get the best effect. | ||
| Panhead_dan |
I seem to remember something in the service manual about how to adjust that cable. I wonder how it compares to your adjustment. I had mine apart a few months ago when I installed a new can. I simply took most of the slack out and ran it rather than to look it up in the SM. My bad. | ||
| 08uly |
"Pushes the valve open" I don't think so but I could be wrong. Cable under tension = "Valve open" Cable relaxed = "Valve closed" My actuator is broken and not operating the valve as it should (threw a trouble code). I had tried adjusting the cable per the manual. | ||
| Conchop |
Try this - take off the cover, start the bike - manually actuate the pulley. Listen to the jingling rattle when the valve opens, then listen to the quiet idle when the valve is closed. ride it and watch it- carefully. You have to really romp on it to make it open. In my opinion, it's a well tuned machine with a computer that somehow makes power and meets emissions. The slightest exhaust leak will cause some loss in power due to a reduction in back pressure. This little accidental discovery has helped my Uly. imstillahappyhillbilly! |
