Strange things man...

[81xsproject]

Ok... So here it is. I am pretty sure already, from blued pipes, that at some stage/s I am running lean. Recently however I moved from about 2500-3000ft above sea level to sea level (the coast). Since the move I have had a problem w/ high idleing when fully warm. The RPMs run up to 2-3k. This is a pain in the a** at stoplights because if I put it in neutral and it picks up, I have to thunk it back into gear again and that sound pains me horribly. I use the clutch to bog the engine down and sometimes it stays at a normal RPM for a while, but eventually pics back up. I don't know the history of my carbs, but I know someone has been in them at least once. I have headers and a 4-1 on the E end and a K&N in the box. Also, my throttle screw is all the way out (not touching the throttle at all). Is there anyway to lower the idle? It didn't do this previously, only after the move.

On a tangential side note... Being a wet clutch, does holding the clutch for long time spans cause any XSive wear. I know on cars it wears out your throwout and pilot bearings, but those are "dry." My stoplight dilemma of late brought this concern to mind.

I hate to keep rambling on, but at a light a few weeks ago I went to go and killed it. With a very quick response, I hit the starter and I am not sure what happened but it made a wierd noise and the number 3 intake-boot vacuum-plug shot off and landed like 15ft away. I kind of saw it and in the concern of retrieving the plug barely noticed that it didn't do the high idle thing with out it. It was wierd and probably totally unrelated, but I wanted to tell everone the story anyway.

JEss

[chevy45412001]

try this

up by the throttle loosen the set screw and put a little slack in the cable. Should bring down the idle. Maybe got bent or broke during the move. Then adjust idle at the carbs,then adjust slack at the hand grip.Just a thought since ya said it didn't do it before the move?.

[81xsproject]

the set screw is already out all the way

[Ken Talbot]

It sounds like the cable is holding the butterflies open a bit. Is there any chance the lower end of the cable got dislodged from its socket and is maybe sitting high so the cable it constantly pulling?
The cable end should sit like this:


If you've had the tank off, or have been messing with the throttle cable, it is pretty easy to get it bound up like this:


This is all it takes to mess up your idle...

[81xsproject]

well I checked it out last night and it is not the cable problem. the carbs seem to close all the way. Any other ideas. can it be the altatude change? What about my other questions?
thanXS
Jess

[Ken Talbot]

Not long ago, somebody had a situation where one of the clamps that holds the #2 or #3 rubber boot to the cylinder block had turned in a bit. It was enough that it was interfering with movement of the throttle mechanism where the cable attaches.
JAT....

[TopCatGr58]

Hey Jess,

Okay, first moving from higher altitude to lower sea level could lean out the ratio, cause the air is denser. And as you've described, it revs higher after it's warmed up, and bikes get leaner as they warm up as well. So....IF your positive that the throttle cable slack adjustment (at the handle) is released enough to allow a little slack, and that the throttle plates are closing completely, then you may want to try turning back the pilot screws a bit, which will richen the mixtures, and may help reduce your runaway idle?? But you really need to be able to verify that the butterflies are truly closing all the way!!

Next, holding the clutch in does put some stress on the throwout pin and bearing, but they are immersed in oil, so as long as your plates are fully disengaging...and not dragging a little, you're not hurting the plates.....and many folks recommend not sitting at lights in neutral....cause you can more quickly react if some cager is coming up behind you and NOT STOPPING!!

You probably had a little backfire that caused the synch port plug/cap to blow off. Although you were getting more air thru the port, it probably wasn't able to suck enough fuel to sustain the high idle? Hope this helps? Good Luck.
T.C.

[scalded dog]

When I have had this problem, the carbs were dirty, and got out of synch, After I cleaned the carbs, and synched them, the Idle problem went away. Later 'Dog

[beegshot]

No solution, but a me too

When my XJ11 is warm, I notice that the idle speed stays high after a run at say 4K rpm. It comes back down after a few seconds, but it sounds like I'm running on a transition circuit in the carbs...like on a Holley 4 Bbl carb. Do these Mikunis have a transition circuit between the idle circuit and the primaries? Maybe that and the new denser sea level air are working together to keep the idle high. My $0.02.

Robert

[81xsproject]

Well I lubed and adjusted the throttle cable as lose as it would go. I can hear the butterflies closing and feel the slack so I am 99% sure it is not the throttle staying open.

[xj11john]

Try resynching carbs.

I would think that if you have your carbs synchronized that the problem would be solved and if there is a problem with the throttle cable that would be found and solved.

You could either get a synchronizer and do it yourself-per the tech tip on synchronizing under maintenance/carburetor, or take it to a shop (just had mind done for $25 bucks at a shop-guy goes to my church)

You may find a fellow xsive or biker that has a synchronizer (if you dont have one) that would let you borrow theirs.

Anyway I would think synching would fix it concidering the thinner air could cause the mixture to be different and require a different amount of air in the intake chambers.

My $.02