Interactive exhaust valve

[VTR1000F_imp]

What is it? I read in some CB1100 review that stock silencer is equipped with such valve. What is its purpose and how does it work? Education time for me! Thank you!

 

[Lord Popgun]

We don't have it in the US. I can't remember what its for though.

 

[the Ferret]

if it's like the one n my FZ it is for emissions and gives more torque at lower rpms

 

[The Spaceman_imp]

It's a valve that opens and closes depending on throttle opening. The idea is to increase back-pressure at lesser throttle settings and decrease it at higher settings. Generally speaking, it'll give you better performance at both settings. And by happy coincidence it keeps the bike quieter when you're putting along, and gives you more sound when you whack the throttle.

Yamaha calls it EXUP, and Suzuki has just added it to the new VStrom 1000 ABS; they call it "SET" which stands for "Suzuki Exhaust Tuning." The CB 1100 does not have the feature.

 

[Deanohh_imp]

I think in some markets it has one.

 

[The Spaceman_imp]

I think in some markets it has one.

I'd be quite surprised, but I don't know for sure one way or the other. I do know the bike would have to have a completely different FI and exhaust setup to accommodate it.

 

[Randy B]

Here is a pic of it.

 

[wildezt_imp]

its that flippy flappy thing that opens and closes controlling the exhaust aperture..to alter the velocity of the exhaust emissions and back pressure...is what i heard.

 

[Tyke57nz_imp]

I think in some markets it has one.

My machine has this fitted, a while back I took the end cover off the silencer to investigate and it is operated by cable from a servo positioned by the collector box. Not sure what will happen if an aftermarket silencer were fitted, guess you leave the servo operational without the cable. Might check with Staintune on that, as one of their silencers is on my wish list. Can take pictures if required.

 

[the Ferret]

I think in some markets it has one.

My machine has this fitted, a while back I took the end cover off the silencer to investigate and it is operated by cable from a servo positioned by the collector box. Not sure what will happen if an aftermarket silencer were fitted, guess you leave the servo operational without the cable. Might check with Staintune on that, as one of their silencers is on my wish list. Can take pictures if required.

Not required but pics would be appreciated so we can all see where it is and what it looks like on the CB. I don't see anything in the pic Randy posted.

 

[Randy B]

Look at the outlet of the pipe. Its not a round hole like on the US bikes.

 

[the Ferret]

Oh I've seen that. that's it? Where are the cables and servo motor that controls it?

 

[Deanohh_imp]

Oh I've seen that. that's it? Where are the cables and servo motor that controls it?

if you look at your air intake duct, there is a rubber cap that is glued in. For the valve control there would be a hose leading to some kind of diaphragm down by the passenger foot rest which actuated the gizmo in the exhaust can. No motor or cables.

Either I saw that someplace or dreamed it...forget which.

 

[rboe]

Used to tune the exhaust so high revving whacko sport bikes (which typically have it, like my buddies GXR) can have some torque at lower rpms. Back pressure can be a good thing for a motor, low down rpm's for in town riding is one place for it.

 

[Pterodactyl_imp]

Oh I've seen that. that's it? Where are the cables and servo motor that controls it?

if you look at your air intake duct, there is a rubber cap that is glued in. For the valve control there would be a hose leading to some kind of diaphragm down by the passenger foot rest which actuated the gizmo in the exhaust can. No motor or cables.

Either I saw that someplace or dreamed it...forget which.

if you look at your air intake duct, there is a rubber cap that is glued in. For the valve control there would be a hose leading to some kind of diaphragm down by the passenger foot rest which actuated the gizmo in the exhaust can. No motor or cables.

Either I saw that someplace or dreamed it...forget which.
The valve:
[/img]

The actuator cable:
[/img]

Cheers

 

[the Ferret]

how about that! very interesting. thanks Pterodactyl

 

[Tyke57nz_imp]

Oh I've seen that. that's it? Where are the cables and servo motor that controls it?

if you look at your air intake duct, there is a rubber cap that is glued in. For the valve control there would be a hose leading to some kind of diaphragm down by the passenger foot rest which actuated the gizmo in the exhaust can. No motor or cables.

Either I saw that someplace or dreamed it...forget which.

if you look at your air intake duct, there is a rubber cap that is glued in. For the valve control there would be a hose leading to some kind of diaphragm down by the passenger foot rest which actuated the gizmo in the exhaust can. No motor or cables.

Either I saw that someplace or dreamed it...forget which.
The valve:
[/img]

The actuator cable:
[/img]

Cheers

if you look at your air intake duct, there is a rubber cap that is glued in. For the valve control there would be a hose leading to some kind of diaphragm down by the passenger foot rest which actuated the gizmo in the exhaust can. No motor or cables.

Either I saw that someplace or dreamed it...forget which.
The valve:
[/img]

The actuator cable:
[/img]

Cheers Thanks for the photos Pterodactyl, do you have a Staintune unit on your machine.

 

[Pterodactyl_imp]

Tyke57nz, G'day.

Yes, I fitted the Staintune last week. Staintune advise, in the fitting notes, that the actuator cable should be removed from the bike along with the OEM exhaust. The Staitune itself is not fitted with a valve. I haven't had it on the road yet as I am off riding for a short while. It may be another 3 - 6 weeks before I get out on the road.

Upon firing the bike up, in the shed, I was impressed by the sound effects. As most members on this forum have reported, not "hoon" loud but a clear, deeper note, just about what I was looking for. Staintune do claim a performance increase. This is immaterial to me, I can scare myself with the neddies that are already available. From what I gather, being at the best a "bush mechanic", the ECU receives no input regarding valve operation. In any case I may fit a PCV. When I am back on the road I will try to meet with VicsCB1100, who was the OP in the Smooth Power Everwhere thread, before coming to a PCV decision. The subject has probably been done to death but any other member input would be appreciated.

Cheers.

 

[Tyke57nz_imp]

Tyke57nz, G'day.

Yes, I fitted the Staintune last week. Staintune advise, in the fitting notes, that the actuator cable should be removed from the bike along with the OEM exhaust. The Staitune itself is not fitted with a valve. I haven't had it on the road yet as I am off riding for a short while. It may be another 3 - 6 weeks before I get out on the road.

Upon firing the bike up, in the shed, I was impressed by the sound effects. As most members on this forum have reported, not "hoon" loud but a clear, deeper note, just about what I was looking for. Staintune do claim a performance increase. This is immaterial to me, I can scare myself with the neddies that are already available. From what I gather, being at the best a "bush mechanic", the ECU receives no input regarding valve operation. In any case I may fit a PCV. When I am back on the road I will try to meet with VicsCB1100, who was the OP in the Smooth Power Everwhere thread, before coming to a PCV decision. The subject has probably been done to death but any other member input would be appreciated.

Cheers.

Thanks for that info, I had the side cover off and figured that it would be a case of removing the lower servo and hose from the upper servo unit on the side of the airbox and fitting a blanking cap. Good to hear that the noise is somewhat improved, did you run with the baffle in or out? Cheers

 

[Pterodactyl_imp]

Tyke57nz, G'day.

Yes, I fitted the Staintune last week. Staintune advise, in the fitting notes, that the actuator cable should be removed from the bike along with the OEM exhaust. The Staitune itself is not fitted with a valve. I haven't had it on the road yet as I am off riding for a short while. It may be another 3 - 6 weeks before I get out on the road.

Upon firing the bike up, in the shed, I was impressed by the sound effects. As most members on this forum have reported, not "hoon" loud but a clear, deeper note, just about what I was looking for. Staintune do claim a performance increase. This is immaterial to me, I can scare myself with the neddies that are already available. From what I gather, being at the best a "bush mechanic", the ECU receives no input regarding valve operation. In any case I may fit a PCV. When I am back on the road I will try to meet with VicsCB1100, who was the OP in the Smooth Power Everwhere thread, before coming to a PCV decision. The subject has probably been done to death but any other member input would be appreciated.

Cheers.

Thanks for that info, I had the side cover off and figured that it would be a case of removing the lower servo and hose from the upper servo unit on the side of the airbox and fitting a blanking cap. Good to hear that the noise is somewhat improved, did you run with the baffle in or out? Cheers

Thanks for that info, I had the side cover off and figured that it would be a case of removing the lower servo and hose from the upper servo unit on the side of the airbox and fitting a blanking cap. Good to hear that the noise is somewhat improved, did you run with the baffle in or out? Cheers
No worries. I left the other (upper) components in place. The lower servo will still be active but, with the actuator cable removed, to no effect. Unless the Gurus on this forum (come on Red Mist et al) convince me otherwise, then thats how it will stay.

All baffles in the Staintune remain in place. I don't believe that the CB muffler has a removable sound restrictor.

Cheers