Update...

[davey1207]

Hey guys. Just an update, over the weekend I sealed my forks, and put new brake pads in. Also tracked down an oil leak, O ring in the neutral switch is cracked.. easy fix. So i've been riding all weekend and im noticing that when i come to a stop my engine wants to idle really high. When i start and warm her up she is idling where she should be (right around 1200rpm) but when i come to a stop she wants to idle at 3-4000rpm! i checked the throtle and it is not stuck. i don't know what could be causing this. any help is appreciated!

 

[HoughMade]

Have you adjusted the idle mixture screws? This sounds like a classic lean condition. On an '81, you probably have (or had) plugs over the idle mixture screws. 3 to 3.5 turns out is a good place to start if you can adjust them. If the plugs are still in, you can thread in a small self-tapping screw and pull them out, then adjust. the factory setting are really, really lean. They need to be fattened up to run right.

 

[davey1207]

Do you mean the the screw that adjusts the idle? that was backing out from vibration and i used a little thread lock and it stopped it. there are other screws to adjust the idle? and (not to sound stupid) what do you mean by lean?

 

[HoughMade]

Nope- not the throttle stop. Lean means not enough fuel with the air.

This are the idle mixture screws- they are between the carb lid and the engine. This view looks straight down:

If you have that plug, remove it carefully and there are screws underneath. Turn them in (right) until it very lightly resists, the turn them out (left) 3 full turns and see how it works- always adjust both the same. This adjusts the amount of fuel in the air at idle and to about 15% throttle opening. If you have screws and no plugs (mine does, but it's a '79 and they started plugging them at some point after that), the process is easier. Just seat them lightly and go 3 turns out.

 

[davey1207]

Hi HoughMade. I tried adjusting those screws to 3 turns out, same thing. i even went little by little as far as 4 turns out and still seamed like the same thing. When i take off in first the bike wants to rev really high and im not really moving as fast as it should be. also she still wants to idle high. other ideas?...

 

[drewpy]

you may have an O ring under the idle screws, take the whole thing out to check (along with the washer in there)

Mike xs has them

 

[davey1207]

what would the o ring have to do with anything...? cracked, leaking air? that sort of thing?

 

[drewpy]

what would the o ring have to do with anything...? cracked, leaking air? that sort of thing?

correctamondo

 

[OliverB]

VERY SMALL o-rings at the bottom of each idle mixture screw. Do a search of the forum. You will find lots of info on how this can make your idle speed behave just the way you describe. Definitely applies to '80 & '81 XS400s.