yics tool q!

hey im not sure you can view this listing

http://cgi.ebay.de/YICS-Absperrwerkzeug ... 1c1ac3c5c4

but does it seem like a good yics tool for my 750?

seller claims it goes to all xjs 550-900cc, but ive read the spacing is different for different models?

its only 20 euros, would it be a good purchase?


PICTURE added:

 

For roughly the same money, you could buy the tool from XJ4EVER and guarantee it's right.
Or you could stuff oily TEE shirt strips in, and buy some really great beer !!
I'll have some Dortmunder Union !

 

sounds like a sweet choise time!

shipping stuff from there to here can cost more than the product itself.

i found few instructions here and i went to thinking of making one meself..

 

"Dass iss ohnee vun ... Vie-Hi-Cee-Esse Tool"

 

I mentioned the same thing to Len when I compared my homebrew one to the version that he sent me. His response was: "the spacing of the seals doesn't need to be precise, as long as they block off the passage between the holes."

To get a better idea of what his tool looks like, take a look at this file -- should tell you what you need to know.

 

Mines a COPY I made from the Real McCoy a Dealer Tech friend let me measure.

The ONE Tool Services ALL the YICS Bikes.

 

I still like the "inflatable neoprene rubber tube" idea, with an old Schrader valve cemented into one end.

It would be easy to make, and less messy than the TEE shirt strips.

Venlis - if you probe the YICS passage with a bent wire, you can make a blocking tool with just 2 rubber elements, positioned over hole #2 and #4.
(inserted from the right hand side)
This would simplify fabrication at the supposed expense of cutting into the replaceable rubber bits.

 

isn't neoprene heat susceptible? In the rubber tube department... I have a set of silicon bake ware. Bread pan, muffin pans, etc. Rated to 600 degrees F.
might have abrasion issues with repeated use.

 

Where exactly is this tool for??? Where on the engine is it used??

 

what? you don't know about the hole in your head?

Without getting into too much argument starting detail (second most contentious subject seems to be how and why YICS works, starts arguments almost as fast as pods) i will say that there is a passageway connecting all four intakes right near the valves. It's a serious of four little ports that go back and connect to a "gallery" of sorts. One long passage that runs right to left through the head and this is plugged at each end with a bolt. in order to do a vacuum sync one must remove on of these bolts, and insert the tool so that each intake tract can have it's vacuum measured independently of it's neighbors.

If your motor says YICS on it, it's got one of these.

 

read here for all you want to know about yics http://xjbikes.com/Forums/viewtopic/t=14757.html

 

All info understood. All new to me, but understood. Thanx!!!

 

Wanna PIC? This at least shows how it works.

"Why" would be directly related to "IF" and that discussion continues; until one of us takes a YICS head and welds up the passages, fits it to a bike, and sees what if any difference it really makes. OR, if somebody who has a bone-stock non-YICS 650 and a bone-stock YICS 650 can tell us if there's any discernable difference? I think it might make a bigger difference on the 550/600s, since the passages are bigger in relation to the intake ports than on the bigger motors, but again, I'm guessing.

 

I've had my '85xj700n for almost 3 yrs.

'Ive had to tune her many times for one reason or another (mostly main.
and " the perfect tune").

I use a rag about 1/2 the time, but mostly for giggles because to be honest, I haven't found blocking the YIC's gallery made a real measurable diff when the valves, carbs, tuning, spark, charging sys, etc are at their best.
Maybe with a neglected or just a real dirty bike/engine it would work
for a half a$$ tuning.I just can't see a diff.

 

Without re-opening the can o'worms; the YICS block-off tool isolates the cylinders so you're not tuning a combination of the one you're looking at plus the other three when their intake valves are closed.

Un-blocked YICS can actually "mask" a slight out of balance situation, because of the "combination" effect.

Do a forum search on YICS and read the debate; I'm going on experience.

 

No can'worms from me

Thats exactly the way it's supposed to work. :wink:

 

Bigfitz, A smaller passage makes a higher velocity swirl. Assuming the YICS port in the 550 is the same size I'm guessing it has less effect.
I read in a review for the XS400R that larger YICS motors have the swirling charge moving at around 4x the speed of the rest or the intake charge but the 400 has smaller YICS ports causing their air to move more like 10x.
Food for thought. I'm not in a position to draw definitive conclusions on the matter.

 

Commentary from someone who kows (in regards to other, related subjects), but since all the various bits in the carbs and engine make up a complete "system", they are all related to each other in various and sundry ways: