Strange detail in the muffler

[Volchkoff_imp]

Dear friends,

I bought new original muffler. But there is a strange detail. Does anyone know what is it?
There is some wire drive to manage it.

 

[Randy B]

It is a valve for flow and sound. It is not fitted in the US so most of us have no information on it. Anyone in Europe or Australia will have dealt with it though.

 

[ingobohn_imp]

In Europe, this device is not part of the muffler, too. I think it was only shipped in Japan or so.
Some kind of exhaust flap to optimize sound and power...

 

[Roger the shrubber_imp]

Four-stroke power valve system - Wikipedia

 

[Cormanus]

There's one on my CB, but I've no idea what it does or how it works.

 

[Volchkoff_imp]

Thank you, Roger.

Very interesting. But I have no servo motor to manage it. I took it away, but sound now is louder than old muffler.
Are there any original insert in muffler to make sound quieter.

I heard that in Australia are special rules about noise of exhaust and it is necessary to use that kind of equipment?

 

[Randy B]

If you ordered it from your local dealer, then they ordered the incorrect part number. Where did you get it from?

 

[Pterodactyl_imp]

Yes Volchkoff, it is an Interactive Exhaust Valve. When I fitted my Staintune I simply disconnected the actuating cable. The Staintune is not fitted with the valve so the actuator works away, ineffectually, unseen and unheard.

There is five pages of discussion in THIS THREAD* some of which, amazingly enough, actually relates to the IEV.

Cheers

*Most of the photos from this thread do not show, perhaps because the thread has been archived. However of passing interest this thread was from the good-old-bad-old-days when Red Mist and the dreaded Tortuga were active on the forum.

 

[Volchkoff_imp]

If you ordered it from your local dealer, then they ordered the incorrect part number. Where did you get it from?

One friend of mine told me, that he have a muffler in his garage. He received it together with his bike from Japan like a spare part. He has sent it to me and It was similar with mine. That is why I decided to buy it. And I was surprised, that even muffler can have differences.

 

[Randy B]

That explains it. The JDM parts are different.

 

[Roger the shrubber_imp]

The US model VFR1200F uses the same valve.

 

[rboe]

It seems it's mostly on sport bikes that like to rev to infinity and beyond. Closed off, it increases low speed torque; the motor behaves better.