So I repaired my yics box in the beginning of spring using epoxy. It held pretty good up until this morning. It went from a perfectly good running motorcycle to a pile of poop over night. I shouldn't say it didnt' run well, it just wouldn't idle. The box leaks internally so I think I'm going to leave it off.
What I did notice while taking a look at things is that I had 135 air jets in it. I removed those and put 130's in it. I also jetted up the carb from a 125 rear to 127.5 rear. I did some mixture adjustment and it seems to run pretty good now. YICS is dead to me.
Would someone please describe the sypmtoms of a failed YICs to me? My '83 with approx. 85k miles has never (to my knowledge) had a YICs related problem. I've never done any repair to the YICs unit. Now the bike has just recently begun to die while idling. It doesn't die suddenly like it's loosing ignition. But rather, kinda misses a few times and then fades away. Holding the idle up around 1500 to 1700 with the throttle will keep it running, but that just masks the real problem, whatever it may be.
Otherwise, it romps and stomps. Starts very good cold. Can be a little reluctant to start hot, but it always does eventually.
Can't give you symptoms for a failed YICS... when mine went I had a lot of other problems with the V, dirty carbs, exhaust leak, carbs not sinked... etc.
It's only one bolt and two hoses to pull off the YICS... then just get some extra hose and a bucket of water and do the test on Lucky's site. Mine had both an internal and external leak.
~Sable
I just pulled my YICS and capped the holes... I would say the bike idles much better and runs the same in any rpm range... as it did before.
My .02...
GlennW
Quote from: glennw on October 04, 2006, 10:18:10 PM
I just pulled my YICS and capped the holes... I would say the bike idles much better and runs the same in any rpm range... as it did before.
My .02...
GlennW
:).......
DITTO.... 8)
I'll keep mine on. With it sealed (internally & externally) I have good, steady idle & it seems to have a little better acceleration than when I've had it off. The way I have it sealed, it will be easy to repair when it leaks again.
A leaky YICS has several symptoms but the only one I can recall offhand is the 'hunting' idle. When mine was leaking, the idle would fluctuate between 1,000 & about 2500 RPMs.
H2O
My new way of looking at things on that bike. If it can break and isn't required to get me from point a to point b, it's coming off.
I took my YICS off and plugged the lines, bike runs great.
Chris
I did see a dyno test somewhere that showed the difference between running one with the YICS & one without the YICS, and there was a slight difference (not too much) at the peak of the powerband. I have been trying to keep that darn thing seald for a while now, but I always keep breaking the seal. As soon as the idle gets a little erratic, I know it broke a seal again.
Quote from: zore on October 05, 2006, 04:36:46 AM
My new way of looking at things on that bike. If it can break and isn't required to get me from point a to point b, it's coming off.
My sentiments exactly!! That's why I also removed the fuel pump...gravity is more reliable!
Brian
Guys not to beat a dead horse but I have both my bikes fitted with copper YICS chambers and they both run great. I can see no way for these to ever fail. I have been running with them for over a year now without any ill effects. I had posted pics and dimensions but I don't believe they are still viewable.
I can definately tell the difference between YICS and no YICS. As Superfly has said the bike runs stronger when in the powerband.
I was able to wire tie them to the frame. I used 1" copper tubing T fitting with a 1/2 pipe from the center. With the 1" end caps this came out to a perfect length 5" to give me a 70cc chamber.? I then soldered a 1/8 pipe threaded adapter into the 1/2 inlet and screwed in a 5/16 hose end. I pressure tested both chambers and everything was sealed tight. Just keep the hoses as short as possible otherwise you may get a backfire problem after the bike sits at an idle for extended periods.
Here are a couple of the pics
Dan
Even when my yics box was sealed and the bike was running well, I could tell no difference in power. The only difference I feel is when the yics starts to leak and my blood presure rises. I then pull it off with all hoses attached and throw it as hard as I can against the closes concrete wall. Then i stomp on it until my foot hurts. I would really need to see some dyno figures of it with it on and off for me to believe it does anything.
I took the YICS of too. For about 2 years I just had a hose between the holes. This spring I capped the holes to sync the carbs and left the caps on because it idles better. No difference in riding either with the hose or caps.
Frans
Why did they add that yics anyway?
While I'm at it... why did they make the petcock so complicated with the vacuum setup? Wouldn't a regular petcock have been much more reliable?
The YICS came about early in the days of concerns over emissions & fuel economy. They were trying to squeeze out all the power they could while using less fuel & making a cleaner burning engine. While YICS has minor effects, it was a cost effective way to experiment.
The petcock is vacuum actuated so you don't need to remember to turn it on & off every time you want to ride. Fuel won't flow (or is not supposed to) without vacuum unless it is set to PRI(me). Just makes it less hassle to go riding & not worry about the bike running out of fuel a little ways down the block - or not worrying about filling the crankcase with fuel if you forget to turn the petcock off.
H2O
Quote from: zore on October 06, 2006, 10:41:04 AMI would really need to see some dyno figures of it with it on and off for me to believe it does anything.
I actually remembered to save a copy of those charts, you can see a dyno comparison here
http://rovmedia.dyndns.org/forum/download.php?id=669
I mostly notice the YICS doing cold starts and when using the choke. I'm still trying to finish my replacement, but progress has been slow, especially recently.
I would never have remembered to do that!
I noticed that my V was running a bit rough fo rthe last few weeks but pretty much ignored it. I thought maybe it just needed a few more adjustments to tune up after Lucky and I synced the carbs - remember, they were WAY out of sync. But...I'm sometimes a procrastinator so I let it go. I had some time today so I pulled my YICS off and dunked it in a bucket of water and blew through it. It looked like a stinkin fish tank bubbler. Leaks everywhere.
This was the YICS that I repaired with Epoxy and heavy duty JB Weld. Both the epoxy and the JB Weld gave out.
I capped off the YICS ports on the motor and started her back up, adjusted the idle and took her for a ride. MUCH MUCH better!
I still think my bike ran better when the YICS was working. I could definitely tell a difference when it was not. I'll probably leave it off for the rest of the season as I'll be puling the motor this winter to polish it up.
david
Oops, forgot to turn on guest downloads for that forum. Sorry to everyone who had to sign up to see the picture. I fixed it so you don't have to anymore.
Going by the dyno, you would probably get equal performance increase from the weight saved by yanking it off. Don't know but given how poorly the are constructed, it's not worth the hassel.
Would have been interesting to see how it would have been had the jetting been played wiht for non yics. My bike runs 100x better now than it ever has. I may try to do the copper yics and see how that works.
I could not get my yikes to hold either till I cut a gasket for it like Lucky had said and used red rtv. I found JB weld too brittle to hold in the center where it tends to flex. I do know that my bike runs much better with it than with out. With the adjustments on the carbs all over the map with these bikes I can imagine some will run better while some see no diffrence.
Bikehandle
Quote from: bikehandle on October 09, 2006, 05:10:26 PM
With the adjustments on the carbs all over the map with these bikes I can imagine some will run better while some see no diffrence.
I'll agree with that. My bike runs better with the yikes. I haven't found the "right fix" yet, and will probably try the gasket and red rtv next, as my jb job wasn't the final solution
Well I went and done it too! After chasing my tail for the past week tearing into the "mistress" trying to find the idle issue as well as the stumble. My YICS is leaking internal as well as external. Now just a matter of tuning up the carb. It just never really ends... does it? ::)
Long story short ---R.I.P. YICS---- :P
Better stll get rid of that terrible carb and at least 50% of the problems of the bike would be cured.
Nics week I'm having YICS burning party. LIBERATION!!!!!
Quote from: Glyn on October 15, 2006, 06:40:59 AM
Better stll get rid of that terrible carb and at least 50% of the problems of the bike would be cured.
I'm super tempted to get a spare set of carbs for my FZR and split em to use on the V
We can get together for a Yics burning Liberation fiesta. I'm down for some black smoke of my frustration.. Nice new wheels by the way Zore. I'll keep the carb. I'm just know getting to understand it. Once I get the mixture tuned I'll be good. Sounds like a jinx..
Please don't burn/destroy/trash them, no matter how bad they are. If you couldn't get them to seal, someone else may be in need of one & can seal them, just tuck them away, or send them out to us.
--Lucky
Quote from: Lucky on October 15, 2006, 01:10:42 PM
Please don't burn/destroy/trash them, no matter how bad they are. If you couldn't get them to seal, someone else may be in need of one & can seal them, just tuck them away, or send them out to us.
--Lucky
Good point Lucky. Send it to me Zore and I'll fix it. Burning it may anger the Vision Gremlins.
Can I paypal you some $ for shipping?
David
Settle down fellas I'm just venting. No Yics burning.. Whats weird is it looks like someone got into it. looks like someone tried to pry it with a screw driver or something. It's leaking from everywhere. I did some reading on Luckys site. I may try to seal it up this winter,time premitting ::). Although she seems to be running much, much better w/out it.
I'm not sure why I would bother fixing it. The dyno shows it does very little and I can't see any difference in how it runs with it sealed up and with it off.
Zore is the spokesperson for the "anti-YICS party". Down with YICS. ;D ;D
it's like unobtainium, only it's unexplanium.. personally, i can tell the difference easily. all else being equal, (meaning both our engines in exactly the same state of tune) i'll bet you could tell the difference. not picking on anyone, but on my bike i've adjusted the valves, updated the fuel system, exhaust, etc, etc ad-nausium... if the bike was 'just running' i doubt i could tell the difference either....
i'm at the point at my bike where i can tell the smallest changes in engine performance...
On both my old vision and on my "new" '83 I notice a fairly big difference in the overall performance of my bike WITH the YICS hooked up and working. It's definately possitive for me. Of course, both of my visions (past and present) are/were running extremely well (well... the old one WAS, then I let it sit for a while)
The old one is running again! Still need to replace the stator, but I got it fired up yesterday. After it was running, I remembered I still need to reattach the MACs. ::) I think I can still hear fairly well, but I haven't needed to listen closely to anything today. May start talking like a Canadian, eh? (lol)
I can tell the difference on my normal ride if the YICS is working right, leaking or plugged off. I'll take the bike with a functioning YICS any day. I agree with Lucky - not a large difference, but it is noticeable - provided you've got everything cleaned, synched & adjusted properly.
H2O
Hey Haunter
Get yourself 2 carbs off a V Max I think they would be perfect for the Vision once re jetted. They are a downdraft CV carb from what I remember. I just couldn't find any for decent $$ when I did my carb conversion.
Quote from: Glyn on October 20, 2006, 03:35:52 PM
Hey Haunter
Get yourself 2 carbs off a V Max I think they would be perfect for the Vision once re jetted. They are a downdraft CV carb from what I remember. I just couldn't find any for decent $$ when I did my carb conversion.
I will takea look, how they sit is a big concern as well, but obviously you probably looked at that as well
I've often wondered if V Max carbs were a viable alternative. Would be very intersesting to find out.
Due to the lack of space between the vee I really think you need to mimic the original carb size/spec as much as possible. I tried Honda CB450 carbs on copper manifolds and there is just not enough space in there. The V is designed for a downdraft carb arrangement. The original dealer ads goes well into this. That's the reason I ended up with a Weber IDF carb. It is very similar to the Mikuni in action. The distance between the barrels and the mounting method is different so new manifolds are needed. Venturi's, jets etc all easily available and replaceable. The carb can be taken apart easily and mine has just sat for a year with gas in it with no ill effects. ie it is made of decent alloy. No YICS to worry about and no dipping/cleaning etc. I still think the Vee Max carbs would work well, since they are designed for a bike, while the IDF's were a common carb on VW beach buggy conversions in the 60's (I believe).
I'm no expert on this and others on the site prob know more about carb tuning. Mine works fine however. Stumble - what's that?
Just an update. After running out of gas with the 122.5 127.5 jets I brought the rear down to a 122.5 as well. Reserve was coming on at about 150-160 or so and the rear cyl ran out o fuel much sooner than the front. Now i'm at 175 miles and no reserve yet. I think the 130's will work well up top for winter and 135's for summer.
Well, I got all my carb stuff mostly sorted out. 122.5/135 front and 127.5/135 rear. So I decided to play around with the YICS. First I made sure it was sealed tight, let the bike warm up and went for a spin with the YICS on. Smooth acceleration, power and smooth idle. Capped off the YICS tubes and went for another ride and it just didn't feel the same. Did not seem as powerful, had some stumble and idled high (2000rpm vs about 1300).
I would really like to do a "blind" test by not knowing if the YICS is on or off....I think I'll go bother Lucky. :D
I'm also going to try syncing it again because my jets were all backwards.
David
Last week I was tweeking my carb synching again and decided to remove the YICS to see how it ran. It doesn't make sense but I couldn't even get the bike started without it. Put it back in and it started back up. Fluke? Took it out after bike warmed up. No starty. Put it back, it fired right up. Whether it truly is a performance part or not my bike doesn't care. It likes that little piece-o-bling between the cyclinders.
Mutt :)
I'd think that in order to do the experiment, i figured you'd have to sync the carbs, adjust the pilots and idle...
Are you doing this or just capping off the ports?
Steve
I connected the ports with one section of hose. It should at least turn over like it's going to start or idle baddly. It doesn't even sound like it's getting fire! It's just a wierd bike but then again it came from Michigan :-X. Sorry PS2, I meant Detroit area. :)
Mutt
You don't want to connect the ports with a single hose unless there is a ball-bearing or something in the hose to block it off entirely. The last thing you want is to have the 2 intake manifolds sharing a connection. Since they are not running at exactly the same time, you end up with a serious vacuum leak in your intake manifold that way. When one is pulling, the other is not and they swap air pressure.
Try to just cap off the ports, don't connect them. You could connect them but clamp the hose in the middle so there is not a leak. The YICS does not have a single chamber in it, it has two separate chambers.
Brian
I put little rubber nipples on the ends and put hose clamps on them to keep them from flying off incase of a back fire.