How long are the YICS hoses supposed to be?

Started by pullshocks, October 13, 2007, 04:38:36 PM

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pullshocks

I have been running without the YICS box, assuming it would be leaky.  Finally got around to testing it today and what do you know, it did not leak.  I have some nice fuel injection hose to use, what length should I cut it to?

QBS

Don't think length is critical.  Long enough to get the job done with a slight bow, but not so long as to kink.

Tanno

I wouldn't think one would want fuel injection hose for the yics. Like it's been stated before, I also agree that the hoses need to flex. Meaning to expand like arteries.

It would help in the higher rpm power band. The yics hoses and box get pressurized before the exaust valve closes and "shoot" that partial gas mixture back into the cylinder when the intake valve opens. This does very little for idle and low rpm, but it does help to give a "boost" around 5-6k rpm.

I believe this was the early experimental of the modern "V-Boost" used on the V-Max models.
Industrial Technician by trade -- Curiosity by nature, tinkerer by choice.
"Handle every situation like a dog would. If you can't eat it or screw it; Piss on it and walk away!" -- Unknown

jasonm.

Tanno, I can prove you wrong on the, "does little at low rpm". Every Vision I have tuned(many)...the idle goes up with the YICS installed. This is after setting the low speed screws the proper way. I won't go into detail. The rpm increase is typically 100- 200rpm on my very accurate digital tach. The '82s are more sensitive the YICS than the '83. The 82's really need it for best low speed running. Plus how many have put their Visions on the Dyno. Well I have...and the YICS does next to nothing on mid range & top. But does clean things up down low. I use the best quality 1/4" gas hose for mine. The glossier the hose the better. Again, I won't go into details as to why.
looks aren't important, if she lets you play by your rules

Tanno

Well, okay. Were's the dyno sheet with and without the YICS connected?
Industrial Technician by trade -- Curiosity by nature, tinkerer by choice.
"Handle every situation like a dog would. If you can't eat it or screw it; Piss on it and walk away!" -- Unknown

VisionaryDan

Jason is right I built my own YICS out of large copper tubing and mounted it under the tank. I had problems at the low end with an occasional backfire. At first I thought it was thought my volume calculations were wrong but it turned out to be that the hose were too long. I shortened them up and mounted the YICS on the frame and they have worked perfectly on both my Visions now for two years now.

So keep use a good quality 1/4" hose, the less it tends to expands during the compression stroke the better.


pullshocks

Do you have the hoses equal length?  Looks like the rear hose could be shorter...am I over-thinking this?

Lucky

nope don't need to be equal length, just long enough to keep them from kinking. 
1982/3 XZ550 Touring Vison, Gold on Black

pullshocks

Casting my vote for "Visions do run better with the YICS box"

h2olawyer

 ;D  Congratulations!

Sounds like you go'er ironed out.  I know mine idles better & feels like it has a little more oomph when the YICS is functioning properly.  Not a big difference, but noticeable.  I have to turn the idle up a bit whenever I disconnect the YICS on mine.  Clamping off the hoses causes about 500 RPM drop @ idle.

H2O
If you have an accident on a motorcycle, it's always your fault. Tough call, but it has to be that way. You're in the right, and dead -on a bike. The principle is not to have any accident. If you're involved in an an accident, it's because you did not anticipate. Then, by default, you failed.

kwells

one day I'll get around to sealing my YICS.  It's just so easy to cap off the nipples....one of the few easy things to fix on the V
...a vision is never complete.

www.wellsmoto.com

jasonm.

Quote from: Tanno on October 23, 2007, 08:25:13 PM
Well, okay. Were's the dyno sheet with and without the YICS connected?
On the wall in my garage. ;D
looks aren't important, if she lets you play by your rules

Tanno

Industrial Technician by trade -- Curiosity by nature, tinkerer by choice.
"Handle every situation like a dog would. If you can't eat it or screw it; Piss on it and walk away!" -- Unknown

Extent

Quote from: Tanno on November 05, 2007, 05:13:05 AM
Well, do share! ;D

http://rovmedia.dyndns.org/forum/download.php?id=669
;)

Quote from: VisionaryDan on October 26, 2007, 04:02:25 PM
So keep use a good quality 1/4" hose, the less it tends to expands during the compression stroke the better.

Expanding??  The YICS is never under significant pressure, you shouldn't ever see them expand.  Soft or old tubing does collapse though.
Rider1>No wonder, the Daytona has very sharp steering and aggressive geometry.  It's a very difficult bike for a new rider.
Rider2>Well it has different geometry now.

supervision

 Extent, I thought you vanished, what's happening man? 
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pullshocks

Quite a drop in power and torque with no air filter

Extent

Quote from: supervision on November 11, 2007, 12:05:55 AM
Extent, I thought you vanished, what's happening man? 

Heh, just life catching up really.  Changing careers, quit my job and then had a bit of a crash in Feb.  I'll have a separate thread on that soon though, it's time to start planning for repairs  ;D
Rider1>No wonder, the Daytona has very sharp steering and aggressive geometry.  It's a very difficult bike for a new rider.
Rider2>Well it has different geometry now.

Night Vision

let us know what you need, I'm sure we have it.... you were nice enough to swap me a kick stand, if I have what you need... you're welcome to it 
if it ain't worth doing it the hard way....
it ain't worth doing it at all - Man Law
;D


if it ain't broke..... take it apart and find out why


don't give up.... don't ever give up - Jimmy Valvano

Tiger

Quote from: Night Vision on November 11, 2007, 04:47:24 PM
let us know what you need, I'm sure we have it. you're welcome to it 

8)...DITTO.
Life should NOT be a journey to the grave with the intention of arriving safely in an attractive and well-preserved body, but rather to skid in sideways, body thoroughly used up, totally worn out and screaming HOOOOYA lets go again baby !!!!!!

'82 Vision, Pearl Orange finish, lots of up-grades!!!