High Idle

[deadog]

Hi, and thanx for the awesome information network you have here! I have been using the forum for sometime, but have been able to locate the info I needed..until now. I bought my XS11 this spring, its an 81, full dressed. I replaced the intake mounts, and cleaned the carbs (first time), as the mounts looked pretty dry rotted. The bike initially had a slight stutter off of idle, nothing bad but made corners sometimes tricky. It also backfired out the exhaust when slowing to stops, with closed throttle. This is why I did the initial work. The bike ran super strong other than that. I also have purchased a sync cluster of vacuum gages from reading this forum. I found the carbs to be out of sync slightly after the cleaning, and fixing that did make a difference, but the problem still existed. Well I removed the carbs again yesterday (third time(triple clean?) and sat down and removed everything but the choke mech. I checked float lvls, they are all equal. The problem I have now is a high idle. The carbs came right back in sync, np, and it runs smooth, but will not idle lower than 3000. I have backed the idle screw out all the way, and have tons of play in my cable. I have the idle bleed jets set at 3 turns right now tho no setting will bring the idle down. Also I noticed, not sure if related, but if I remove the vacuum gage hose from carbs 1,2 or 4 it changes the engine, but removing the #3 makes no changes. I wonder if this is a connection as the others are sync'd to that carb. I did not have the high idle until the second cleaning, so the change came at that time, and now I am stuck with it. I have used the search forum, but only found others with similar problems, and not a lot of solutions, I did try the ones offered tho.

Thank you in advance for anything you may offer

Mike

btw I live in Central NY and so far my XS11 is the only one I see..

[pggg]

Unplugging sync port No 3 should 'stutter' the motor same as the other three do, but 3000 revs is high if the butterflys are all closed off with the idle adjuster, a sticky cable connection at the carbs or twistgrip not fully closing?

[deadog]

Nope, the cable is slack, and yeah the butterflys are closed, I do think there is a connection to the #3 carb not being affected by the vacuum hose being removed, if its not acting properly all the other carbs sync'd to it will be off, hence the high idle? But what will cause the #3 to be unresponsive to the vacuum hose being removed?

Thanx for any help..

Mike

[Ken Talbot]

It sounds like some part of the linkage between the carbs might be hanging up on something - maybe a hose clamp on the manifold side? Either that, or there might be a vaccum leak, again maybe at one of the carb-to-manifold mounts.

[pggg]

Originally posted by deadog
Nope, the cable is slack, and yeah the butterflys are closed, I do think there is a connection to the #3 carb not being affected by the vacuum hose being removed, if its not acting properly all the other carbs sync'd to it will be off, hence the high idle? But what will cause the #3 to be unresponsive to the vacuum hose being removed?

Thanx for any help..

Mike

Well the butterflys control the idle speed, if there's an air leak causing the high idle, then it's likely No 3 leaking...

[prometheus578]

check to see if the vacuum port cap for #3 is any good, I mean, not leaking.
Also.. check to see if you're running on all cylinders at idle. Let the bike warm up a little and spray a little water mist on the headers. #3 is probably dead at idle, but roars to live once it's past the idle circuit.
If it's not vacuum related, time to pull the carbs again and check out #3's idle circuit. (Broken tip on the pilot screw?)

[deadog]

Originally posted by Ken Talbot
It sounds like some part of the linkage between the carbs might be hanging up on something - maybe a hose clamp on the manifold side? Either that, or there might be a vaccum leak, again maybe at one of the carb-to-manifold mounts.

Well thank you all!!! It turns out that when I had replaced the intakes, the gasket on #3 had swiveled down off of the bolt. There was my leak! I made a new gasket, bench sync'd and putem on again, this time my idle was back... Resinc'd with the gages and much better, back to lifting the front on throttle snap..wooeee! Now I just have to pickup a colortune to dial those lowspeeds in. Thanx a million guys and keep up the advice..spoton!

Mike

[TopCatGr58]

Hey Deadog,

Save your money and adjust your pilot circuit by EAR(Ken's tip), see the tech tips, it's already idling well, just doing it this way will set them up just fine! I don't know about you, but I don't spend much time IDLING!
T.C.