My other problem....

[markjs]

My XS will not idle. When you set the idle warm. it might be fine for as much as a minute but then it will either jump up just above 2k rpms (usually only if you give it throttle but sometimes on it's own), or dip below 1k and die. I have checked the front boots, with WD40 while running. While they are cracked, there appears to be no vaccum leak. All vaccum lines are brand new. The trhottle spring is strong and I have lubed that all so it moves very freely. I changed the throttle cable to no avail.

The carbs have recently been cleaned and blown with compressed air and they looked no worse than any other carbs (and I have done quite a many in my time). The only thing I haven't done is tried to run it with the airbox off to actually look for sticking slides. I will likely check this soon but haven't yet, but I honestly don't think that's it.

Is their any electrical problem that can cause this issue? The bike is rife with electrical issues.

[Dragon Tamer]

Mark,

I would guess that you need to sync the carbs. A refusal to idle properly is one of the first signs of out of sync carbs. One other thing to check as you have all new vacuum lines is that they are installed to the proper ports.

[markjs]

Oh god here we go again with the carb sync BS. I have seen too many bikes and too many farther out of sync carbs than these, that idled far better than this. These are bench synched. The laws of physics make it impossible for the carb sync to be the only issue at hand here.

I know some of you get pissy when I tell you it aint carb sync, but so far it's me one all of you carb sync people zero, because when I asked about my Kaw it turned out not to be carb sync even though I got told over and over about syncing the carbs.

So here's the deal; if anyone local wants to help me synch my carbs with your tool, I'll bite and I'll bet you $20 it has no signifigant effect on the problem.

You see I have revived too many back yard rust buckets and I have bench synced so many carbs and not one of them ever exibited these symptoms. I know well how much a carb synch can effect things and there is no possible way a carb sync problem could cause this radical of an idling problem.

I hope someone local can help me synch the carbs, because not only will I have synced carbs and also be able to put this nonsense to rest on the board, but it'll be one of the easiest $20 I ever made.

The Yamaha XS1100 does not have special "magically different" carbs that are 50x more sensitive to synching than any other model. My Kaw has very similar carbs, and they are bench synched exactly the same as the Yamaha and until it came up with it's current electrical issues, it idled like a dream, rock solid. There is no way in hell this is a carb synch issue. If anyone has any other ideas I'd appreciate it, and I do appreciate the effort, all the same, but please I do not want another debate about carb syncing.

Seems to me some of you would think the seat is cushier and the spedomter more accurate and the headlight brighter if only I'd sync my carbs.

I'd be glad to sync them, if I could, and I am sure the bike would be a little better off for it, but this is not the problem with the idle. I know it. I am also not able to pay for it to be done nor afford a tool anyway. If someone can help great, but I also need help with this problem which is much deeper.

[Ken Talbot]

Re: My other problem....

Originally posted by markjs
Is their any electrical problem that can cause this issue? The bike is rife with electrical issues.

It is a long shot, and I'll still put my bet on a sync problem, but you might be dealing with an intermittent broken pick-up coil wire. These engines will run quite on two cylinders, then all of a sudden run a whole lot better when the other two cylinders join in. Similarly, if it is just barely hanging on at idle with all four working, and you lose two, it will just quit. What have you done so far to check your pick-up coil wires?

[mro]

Weird things can happen on the electrial side. Most common due to corrosion at connectetors and grounds. Worth the couple hours to clean em all just to eliminate them as a problem or potential problem. Alternater connector in particular will melt if it builds enough resistance due to corrosion (located behind fuse box)

I've as yet not had an electrical problem that would cause the idle one time to increase and another time decrease.

So far problems that were electrical have all caused the bikes to miss fire, die or not start. Coils, pick-up wires and TCI have done this.

Might hook up a voltage meter and see if the voltage is swinging up/down enough to affect ignition.

The idle/enricher circut rules the carbs below 2000 RPM so sticky slides unlikely.

mro
good luck

[ccogswel]

Well if I may throw my two cents worth in.

If the bike won't idle but rev's up fine without cutting out I'd say it's the carbs. As long you don't have sticking slides.

But if it does cut out when you give it a twist I'd say then check for electric problems.

[planedick]

Wishing

I wish I was close to you I would snap up that $20 in a heart beat. Synchronizing is very important followed by idle mixture adjust followed by final synchronizing and then it will even idle at 500 to 700 rpm reliably if the compression is even on all cylinders.

[wa407mpp]

I think you guys should just ignore this guy , he comes whining for help , then tells you your wrong ,let him solve his own problems as far as I'm concerned he's just wasting everyone's time, I through trying to help him.

[mro]

I think you guys should

Play nice...
I'm curious what the final result will be.
If you run'em off I'll never know


mro

[planedick]

You think?

Mro, I doubt that if it is Synch and he has it done he probably won't admit it anyway after ranting so much about it not being necessary so you probably will never know what the result is.

[wa407mpp]

I was being nice, and I do know what is wrong, it's a 2 min. fix, but mums the word.

[81xsproject]

I decided pulled the plug in his last thread. Let Mr. Know-it-all figure it out. Sorry, there are other members that need help and listen. Peace!

[markjs]

Look you screamed at me for a whole thread about it being a sync issue and last time you were all wrong. I am not a total novice. If synch could cause this and I have never had this problem with a bench synced bank of carbs before, why would an XS be different?

So wa407mpp, put your money where your mouth is and help me sync them! I live in walking distance from the Honda shop. You are absulutely wrong, as it is not a sync issue and you will lose $20, but at least you can report back. I would be happy to admit I was wrong anyway, whether you think so or not, I just get tired of being told it's a sync issue when I know better! Convenient that you are through trying to help me when it might cost you $20 and some public embarrrassemnt. The other day you were sure willing to help me sync them!

Tell me when have you ever seen a bench synced set of carbs do what I describe (almost 3K variation at idle)?

[prometheus578]

"Let this thought synch in..."

Now that's good!
Ok, maybe not.
Sorry to say, or maybe not, but as someone who used to get paid to do this stuff, I have seen this effect.
Carbs being funny creatures... but there may be other issues involved... still carb related.
Also, I have seen in my travels, Markjs, carbs that I have meticulously cleaned (and presynched) being taken off the bike and gone through again... curing whatever problem I missed the first time.
A carb synch or a "bench synch" is only as good as the rest of the system is.
Here is what I recommend:
Start the cold bike.
Have a spray bottle of 409 handy.
After a minute, start lightly spraying the header pipes.
What I believe you will find is that one pipe remains cold.
This one pipe then becomes hot when the RPM spikes... for obvious reasons.

If the engine starts in the high idle mode... douse the pipes with the liquid till they all sizzle/evaporate the same and continue to watch. When the RPM spikes downward, you will again see a pipe that doesn't sizzle like the others.

What you have is a cylinder firing intermittantly.
And yes, it could be your bench synch.

A poorly synched carb will tend to cycle like this as the engine fluctuates. One cylinder starves putting an RPM strain on the other three. It catches and fires... revving up. Now the other three strain that one cylinder's efforts and the RPM flucuates downward again.
A similar thing in the lawnmover repair trade is called "hunting"... trying to stabilize itself while "hunting" for fuel. This applies to one cylinder Briggs and Strattons as well as four cylinder Yamahas.
It could be the carb synch.
It could also be a fouled spark plug intermittantly firing.
It could be a bad spark plug.
It could also be your pilot circuit.
Either way... what you have is a cylinder that only fires when it feels like it.
By doing the water/409 test you will identify the cylinder... and the carb responsible. Pull the carbs and clean them again... paying special attention to you know who.
Depending on which style of carb you have, (and I'm too tired to research what year bike you have) the tip of the pilot screw could be broken off and plugging the pilot hole. The rubber O ring on the screw could have fallen off in the hole and be boogering things up.(I've seen carbs with two o rings, as the previous person failed to get the old one out when cleaning and just put in another one as he didn't see the original still sitting down in the well. I've seen a lot of things!
There is a reason behind the term "Triple Cleaning Carbs". I don't agree with it as I feel carbs should be cleaned right the first time.. but no one here(other than me) is perfect.
(I just don't advertise when I make mistakes)

What you need to do is pull the carbs, re-clean them, bench synch them as is proper and try again. (With new plugs installed)
What you don't need to do is say...
"I've cleaned them once... I'm not gonna clean them again."
This will not help you... and then neither will I.

General thoughts: We must recall that a seemingly snippy attitude is only the frustration talking. We've all been there. Some people only have a shorter distance to go before they're at their wit's end.
Frustration is understandable. Failing to heed advice though, isn't.
Test, clean, retest and report back.

[rockhauler 2006]

my other problem

as far as the weather checked boots you can use black silicone and put a coat over the entire boot and it will not only seal them but prevent the need to replace them if you can find them in any better shape