Very High Idle

[fauxamish]

I recently added a full Yoshimura exhaust, then put in a 170 main jet (air/fuel screw is out 2 1/2 turns). I put the carb back on the bike and when I fired it up, it idled at near full throttle. I adjusted the idle screw, but that did nothing. I also turned the throttle cable adjustment all the way in and all the way out of the carb, but that did nothing either.

I ran out of time yesterday to tinker and I can't get at it again until Saturday, so I was hoping for some ideas as to what I can try. I was thinking that it could be that the float is stuck.

I also noticed that the bottom of the carb was damp with gas and that the throttle seemed stiffer than normal.

Thank you for any insights that you may have.

[Banshee_370]

make sure the slide moves freely up and down when you push the throttle, i had a slide get stuck 3/4 up the carb. all it took was a little carb cleaner as lube and work it up and down.....

[fauxamish]

I took the top cover off and the slide was all the way down... it moved when I pulled it up.

did the cable that adjusts the idle break? my friend had this problem on his 400ex...

[fauxamish]

No, it does not appear to be broken. I took the side cover off to look at where the throttle cable attaches and looked at the idle adjustment screw. It would turn in and out. I backed it way out and it wasn't even touching the stop on the throttle. I could turn it way in and it would touch the throttle "thing" for lack of a better word. I didn't think to try hitting the throttle while it was running, so maybe the cable is sticking? I was going to lubricate it anyways.

[carpenter2008]

i had the same problem with high idle. i had to loosen the cable so it would rest on the stopper. then adjust the cable by the one by your thumb

[katch26]

pilot jet can cause a hanging idle too

[fauxamish]

It ran fine before I jetted it (other than being lean) so I don't know that the pilot jet could be it. I did not change that at all. I do not have my Clymer with me, so I loosen the cable by turning the "L" shaped pipe thing all the way in, correct? I did that when I was trying to fix it and nothing happened. I think that I will lubricate the cable and the throttle slide. I will also check the float. Thanks everyone for the insights.

[katch26]

if you rev it up does it pop on the way back down....if it does that and hangs its a lean pilot circuit