Will ------ Exhaust pipe valve

[Mac900]

Hey Will,

I've noticed that on the 1098/848/Hypermotard there is some sort of a device in the exhaust pipes on the way to the rear cans that look like it might be some sort of flap or valve. Looks to be operated by an extension or addition to the throttle cables. What is it and what does it do? I'm sure if a full system were installed this piece would not be used but it looks like it'd still be in action if just slip-ons were installed. That is unless it were disabled with the slip-ons. What's up with that?

[teddy037]

I'd imagine it's like the ex-up valve, or whatever it's called... keeps some back pressure for the low end, ECU tells it to open the fuck up when at higher revs for flow

[lurkingforyou]

depends on which manufacturer you ask.
when exup valves first appeared on yamahas and suzukis, hey where up by where the pipes colected.
now on certain models they are farther back.
on the new r6 for example it is post cat, the effect this would have on the moter is questionable.

now as far a ducati is concerend, and this is what i was told by the national service manager at my last training in san fran, it is a noise controll system that mostly comes into effect with engine braking.

so there you have it.

now if this question is based on performance gain possibilities, DON"T MESS WITH IT, it is conected to the ecm and will throw a bunch of funky codes if it is messed with, and i will have to file a claim and so on. plus i think there is no real gains or losses accociated with it.
full systems do eliminate it, but they also have totally differnt maps than half systems.

[teddy037]

noise ctrl?

ghey!

>

[Mac900]

Interesting you guys and thanks for the responses.

Now I'm not interested in this for performance gains. I completely realize that if that were the goal then there would be a completely new exhaust system installed from the exhaust manifold rearward. If anyone were to ask my advice /opinion about power increases I wouldn't hesitate to recommend a full system and new ECU.

If the ECU was driving this valve I'd expect to see wires and stepper motors. It's very possible that I've missed those but so far I see nothing but brackets and cables. At this point, and I will admit straight up that I could be wrong, there is nothing I see that indicates electronic control or sensing feedback capability.

If changing this control will set off fault codes and MIL lights then how does the ECU know? If there is no electronic feedback to the ECU then it cannot know if the flap valve is working or not, or even what position it's in. Yes? No?

So far my curiosity is only being academically driven. No ulterior motives other than understanding the system and the design behind it. So far, that is.

[teddy037]

exhaust valve pos'n might just be related to TB pos'n?


I'm a machinist, what do I know about motors? :angel:

[lurkingforyou]

there is a stepper motor and wires from the ecu to the exhaust valve control.
as point of reference, here we go.
i have installed full and half systems on bothe the 1098 / 848 motor and the hym system, both utilizing this valve.

1098 /848 the full system is really benificial in agressive track type riding, otherwise half is what i recomend

hym the full system is geat while the half system cures the related problems with epa requirements, full is the way to go unless you prefer the two pipe look.

[Mac900]

Cool. I'll be out with the flashlight later but not tonight. I've still got a cold and I should have been in bed a half hour ago.

[lurkingforyou]

ok, if it is the hym, push for the full Ti [thumbsup]

[Mac900]

As fate twists and turns -- Lo & behold my buddy showed up with a Termi slip on system for his Hyper three days after this thread started. He didn't tell any of us he was getting it. I knew he was interested in the slip on even though I always pushed for the full system. The thing is he says he's not that interested in more power and absolutely doesn't want it loud. ( ??? ) OK, I saw the stepper motor up under the back of the seat & tail light assembly and all the wiring that goes to it. Quess who was drafted to install the pipes?

The terminology "slip on" is not quite correct. It goes but it's not exactly straight forward. It hasn't helped that the end of the pipe that slips onto the exhaust pipe was dented in shipping. It's a good thing I have a shop with tools that can make pipes round again. It is a very snug slip on and all the pipe angles have to be just right to get it to go.

Now, about the ECU. Should we just leave the stock one in and bring it down for you to install Will? Would the engine even start with the new ECU or does it have to be flashed with the keys before starting the engine? Is it plug and play and then you set all the final tune specs? He's figuring on having you finish everything along with doing the 600 mile service.