YIC.... Yiks

[cpudoc]

I have read about taking this out of the system, what is it and how do I take it out of the system??????

 

 

Thanks

[Neil86]

YICS-Yamaha Induction Control System. These were on the 83-85 Venture (and other models of that era). Essentially there are 4 chambers one for each intake that sit above the front cylinder heads. The theory is when a cylinder intake valve closes, some of the intake charge flows into the YICS chamber via the hose, when the valve reopens, because the YICS chamber is at higher pressure the charge flows out to the intake causing a swirl and better combustion.

You can remove the hoses at the intakes and cap the intake nozzles, and leave the YICS chambers in place till you need to remove them to do valve cover gaskets etc.

[Venturous Randy]

I plugged mine and it runs a lot better than it did. Just get some heavy duty plugs.

RandyA

[cpudoc]

Just plug the outlets near the carbs? I assume there are 4 ports that I need to plug?

[mbrood]

It's a large, four segment, black plastic canister... sitting right above the front cylinder's valve cover. There are four relatively heavy hoses running from the back of this "box" to the engine, one from each segment to "it's" cylinder. You want to plug each line at the engine, effectively removing the YICS chamber.

 

http://www.bergall.org/temp/venture/yics.jpg

[dkaiser]

And I assume it would be a good idea to disable it?

 

D

[Venturous Randy]

And I assume it would be a good idea to disable it?

 

D

 

Nope you can't disable on your 87 because there is not one there!

RandyA

[Gentleman George]

For once I'm glad I don't have one!!!:rotf:

[MikeM8560]

Why undo it? is it bad? sounds like a boost bottle on my sleds i had up north.

[GigaWhiskey]

If I plug my YICS ports, will I need to do the Jason Mod unitl I can properly get in there to fix it? Or, are both a pain?

[Neil86]

Giga..

Nope...just plug it. 86-93 did not use YICS and run fine.

I think Yamaha decided the benefit was minimal to the YICS setup....and dropped it.

 

Mike...

If the YICS chambers aren't leaking you can still run with it....the problem is getting a good test on them.....probably a vacuum test with chamber hot and engine running to get the vibration best.

They tend to fail on the seams as they age.