Another YICS

[Superfly]

I got this YICS off of another Yamaha V-twin.  I have no idea what it came from (Virago maybe...) And It worked really well.  It developed a leak, and I went to fix it, I noticed that the chambers were not even.  It is also a little thicker then the one that came stock on the Vision.

[Superfly]

Just put it back on my bike, and my bike runs much better with this version of the YICS than the stock YICS.  It is also about 3/4" - 1" Thicker than stock.

[silicon_toad2000]

the unequal sizes of the chamber could be to do with the intake valve timing of the engine.
Even on our V there is a time when both intake valves are open. If the manifold was joined then there would be less vacuum when one cylinder sucked than the other so it would need a larger chamber to get the same volume of air injection.
With our bikes, one cylinder starts sucking and then before that one has finished the other starts sucking from the air cleaner assembly which allready has a low air pressure so the second cylinder's manifold would have a slightly higher vacuum that the first.

I just reread this and I'm sure if I didn't allready know what I was trying to say I would be very confused, but I'll post it anyway.