YICS - not again?

[randy]

Ben and I are getting ready to do some surgery on his 82 XJ, so I looked up the YICS tool posts, but I found different dimensions for the tool. Norm Koke's post has the middle spacers at 4-1/2" long, but a subsequent post has the deep one 6" and the shallow one 4". Which is correct?

Also, If the expansion hose between 1 and 2 carb blocks off 1 and 2, what seals 1 from outside air? I don't see any seal at the outside fender washer?

[blue giant]

Randy,

Whaen I made my YICS tool I followed norm's dimensions and it worked as it should. I believe when the rubber blocks the hole between carbs 1 & 2 it is also blocking carb 1 from outside air as you are really blocking the ports to the main balance tube.

Paul.

[randy]

Thanks, Paul.

[trbig]

Depending on how advanced the surgery you are doing..... Just plug those ports off?? I'd sure hate to have to mess with that tool every time I mess with my carbs.... and HOPE that it was actually sealing off things like it's supposed to.

Tod

[randy]

No, the head is not coming off, but if it was.....

[madmax-im]

YICS makes me sick....

Heck I'd just as soon throw those Suzuki GSXR750 slingshot carbs on there...how much harder could that be ???

[AlanB]

Hi Ben,

You will still need to balance 'em..... so you still need to block the ports.

If you run a tape measure across the head, you should be able to figure out which sizes you need to block the ports on your head.

AlanB

[madmax-im]

Originally posted by AlanB
Hi Ben,

You will still need to balance 'em..... so you still need to block the ports.

If you run a tape measure across the head, you should be able to figure out which sizes you need to block the ports on your head.

AlanB

Hey Alan;
ok not totally following you on this...keep in mind that i have not yet read over the procedeure for doing the carbs...I'm kinda relying on randy to know the ins and outs of this...he will hopefully guide me through it and then I might obtain a degree of enlightenment...so how much more difficult would it be to do the gsxr carbs?No doubt I would still have to rejet the slingshots and also figure out my throttle and choke cable setup...so sounds like its more work...at this point I wiil save the slingshots for another time...ok so I guess I answered my ??

[trbig]

The YICS is between the carbs and the valves, so it would come into play no matter which carbs you have. Sorry...


Tod

[madmax-im]

trbig...alan...I get it now...just a tad slow tonite...

[randy]

Ben, don't worry about the YICS tool, I'm fabricating one.

[trbig]

You could always just fill that tube up with silicone!

*Evil instigator...


Tod

[madmax-im]

Pros and Cons to YICS

My limited understanding if YICS is that there is some extra porting in the heads of the '82s' for emissions ...if Im not mistaken YICS means Yamaha Induction Carbueration System...but not sure exactly how it functions.Most likely there is a big debate as to its necessity...be interested to hear what the prevailing opinion is on it...

[madmax-im]

Re: Pros and Cons to YICS

Originally posted by madmax-im
My limited understanding if YICS is that there is some extra porting in the heads of the '82s' for emissions ...if Im not mistaken YICS means Yamaha Induction Carbueration System...but not sure exactly how it functions.Most likely there is a big debate as to its necessity...be interested to hear what the prevailing opinion is on it...

It does sound like its' a PITA though

[AlanB]

Hi Ben,

It is no more than a set of passages through the head casting, linking the four inlet tracts together.

I never really figured out how (or if?) it really helped the emissions, but it is easy to see how it stops you synching the carbs.........

AlanB