YICS

[Agonoize]

So my Vision is now running but currently without the YICS.  My question is, is it better to have the YICS air chamber on or off? does it matter? would it make a difference in power or fuel efficiency.  Or would it just be best to leave it off?

[Re-Vision]

If you have one that doesn't leak, it would likely make your engine run a little smoother. A lot of Vision riders don't use them because a good one is hard to find or repair and the improvement is not that great.    BDC

[Agonoize]

I see, that makes sense thanks.

[Coil Coyle]

It is fun to pop 'em apart and try your favorite sealer.
Building new ones let you change volume.
A length of hose might do the same?
Think "a little puff into the port at low vacuum".

I glue them and run them, but Ron McCoy's copper pipe equipped versions look way cool!

$0.02
Coil

[Raj1988]

Any pictures of aforementioned copper pipe?

[Tiger]

 :) Plug ports with vacuum caps and fire that YIC's in to the recycle bin...lol I don't run one on "The Mistress" or any of my rebuilds.

Some guys here swear by them and some, like me, think of them as a weak link...its one of those "agree to disagree" things really... :-\

          8).......TIGER....... 8)

[YellowJacket!]

This is probably one of the hottest debates about the Vision.  I feel that my bike runs MUCH better with it and I can definitely tell a difference when my YICS is leaking.  I have repaired several; for myself and for other members and my repair job - which in part I got from lucky's website - seems to work quite well.

I use a utility knife to score along the seam until I can separate both halves.  It takes a long time but is easier than cutting it in half with a saw.

Next I use 80 grit sandpaper taped to my garage floor and I put one half of the YICS on it and sand it in a circular motion until the surface is flat and good and roughged up.  Lucky's site has a diagram and instructions to make a gasket which I do next.
Once both halves are sanded sown and the gasket is made, I apply red RTV to the edges of the YICS and sandwich the gasket in between.  I clamp both halves together for 48 hours then mount it back on my bike.  All is well and YJ runs fine.

David

[Agonoize]

Thanks for all the posts.  I'll play with the YICS a bit and if i get no where I will leave it plugged up.

[YellowJacket!]

Thanks for all the posts.  I'll play with the YICS a bit and if i get no where I will leave it plugged up.

Or you can send it to me and I'll rebuild it for the cost of shipping.  :-)

David

[Raj1988]

Can i get one too David??

[YellowJacket!]

Can i get one too David??

If you have a YICS for me to repair, send it to me and I will fix it. I can PM you my address.

One caveat, I'm finishing my Organic Chem class and have a final coming up so it may take a week or two (mainly due to my work schedule) before I can get it repaired and returned.

David

[Brian Moffet]

If you have a YICS for me to repair, send it to me and I will fix it. I can PM you my address.

If I drop off my 83, will you fix the YICS?       ;D

Brian (just kidding, it's not broken)

[YellowJacket!]

If you have a YICS for me to repair, send it to me and I will fix it. I can PM you my address.

If I drop off my 83, will you fix the YICS?       ;D

Brian (just kidding, it's not broken)

Sure!  I'd like to finally meet you anyway.  I can cook us up some burgers too.  Oh wait, I've been banned from cooking burgers but I'd still like to meet ya.
8)

David

[Raj1988]

i do have one, and i will send it to you. Anytime before August 20th is good :)

[ejether]

I just took my  YICS off. Right away I noticed better throttle response and I felt more power, right up to and through that dead spot 'stumble' at 5K which is especially bad on my Vision.

I took it on a long test ride (250 miles or so) and it ran great until I had to idle in slow moving traffic... then it started dying and was hard to start. Then, this morning, it was very hard to start, was running WAY rich and popped a few times before kicking over.

1: I want to try a copper pipe YICS but I'm not sure what that entails. Does anyone have photos of that?
2: If I choose to leave it off, what sort of tuning can I/ will I need to do to make it idle a little better and start more easily?


Any thoughts folks?

[Extent]

Copper pipe YICS is dead simple, solder up two lengths of copper pipe that have the same internal volume as each respective YICS chamber with a barb on each one.

I don't believe there's any major tuning changes to be done without a YICS, I would just do normal external maintainance on them (set pilot jets, resynch, reset idle)  Someone posted dyno graphs of both with and without a YICS a long while ago, the difference is obvious but minimal. 

As for my opinion?  Set up your bike up to spec without the YICS, then plug the YICS (a good, sealed YICS) in and see what happens.  Your idle will jump up, that extra power doesn't come from nowhere.  That's all I need to convince me that it's worth having if you can get a good one, I also find that the bike starts much easier with it on.  It's not worth being religious over tho, when I have leaks I run without (and I always carry vacuum caps with me just in case)  My YICS is currently half of stock size while I was working on a leak proof alternative.

[Lucky]

I just took my  YICS off. Right away I noticed better throttle response and I felt more power, right up to and through that dead spot 'stumble' at 5K which is especially bad on my Vision.

I think this is very telling, but not in the way you would think..

you took off your YICS? Why? to see the difference, or because it leaks?  if it leaks & your performance improved when you capped off the ports... well duh...

if it didn't leak (are you SURE?) and it runs better, I would guess the engine tuning wasn't set correctly to begin with (no slight intended to anyone with this last comment)

--Lucky

[Rikugun]

Lucky's last  comment had me wondering about the state of tune of any particular Vision. It seems no 2 are identical. One person's setup may render the YICS more or less effective than someone else's. Person A removes his with no discernable difference while person B "feels" a noticeable difference. This of course also relies on the precision laden science of "seat of the pants" tuning.

I'd like to see those dyno results!  :)

[Agonoize]

Well after 3 different YICS's 1 I know doesn't work now, 2 that should work I still find my bike runs better without it.  So I left it capped my only continuing problem seems to be overheating or something related I can't figure out.  It won't ever hit the red line now that I have a switch for the radiator but once it crosses the 3/4 green it will start shutting off on me unless I keep it above 3k rpm. If anyone happens to have any thoughts on this one Im all ears.

[Re-Vision]

If I read you right, it seems as though your problems with the engine began with installation of radiator override switch. I would remove the switch and see if RPM and engine shutdown problems go away.   BDC