odd throttle and idle problem. Slightly stumped.

[LAsunbird86]

So, I just finished my valve adjust and 5*advancer and everything works great!

The only problem is, now it wont idle without the idle adjuster turned full out, and then it only hits 1500rpm. If I warm it up with the choke it will hit about 2000rpm, but it will die if I take the choke off. (it did not do this before I did my valve adjust).

I also noticed that my throttle response (crispness or sluggishness) is directly related to where my idle adjuster screw is. I know this does not make sense, and when the air box is off and I am looking at everything with the idle adjuster turned full out, the throttle snaps closed.
BUT when the bike is running, and the idle adjuster is turned to keep the bike from dying...its hoooorrrrrribly slow to come back down from revving it.
I found a pinched throttle cable, but I did fix it. I still cannot figure out what has happened to my idle, and why the idle adjuster affects the responsiveness. i have yet to ride it as I'm not sure It would get very far as it is.

As it sits, my bike will barly pull 1200rpm idle, with the adjuster turned fully. and I have the throttle response of a slug.

I am going to go check and see if I left any vaccum hoses off...AGAIN.
Thanks for any and all advice

[jbo197]

Feel for you bro ....
Have the same problem of her not wanting to idle ~
Idle adjuster maxed out, she idles, but that means that she is past the idle port and past the transition ports and kind of running off the mains.
Like you, I am still in search of help.

Surely someone knows something.
I have cleaned the carbs 3 times, with the same results ~

[rexazz2]

check ALL hoses
I know guys have experienced odd problems due to hoses, especially the vac hose to fuel petcock

[jbo197]

Me, remote tank ~

[arsenic]

did you plug the vacuum hose on the 4th carb? If your running a remote tank and you don't plug that hose, stange stuff will happen.

[jbo197]

Have Morgan Carbtune attached to all 4 Carbs ~

[md86]

I also noticed that my throttle response (crispness or sluggishness) is directly related to where my idle adjuster screw is. I know this does not make sense

Sure it does ! Basically when you turn that screw up , it's kinda like holding the throttle ope . If you're holding JUST a little throttle after you rev it , it'll come down slower than if it snaps fully closed .
Anywho ..... Was it ok before you messed with it , and what did you do when you messed with it ? It's ALWAYS related to something you did .

[LAsunbird86]

well, it did ALL of this when I first got it, but I got it to idle after a few hours of tinkering and adjusting by playing with the idle during warm up and then turning it back down after it ran for awhile. It wont even do that now.

It has done the thing with the throttle response and the idle adjuster since I have had the bike. instead of vrooom, its vroooooooooommmmmmmmm.

[Kreylyn]

Did you make any changes to the valves when you adjusted them? Has the bike ever been worked on or adjusted before? If you don't know if it has, assume yes. If the valves were out any significant amount, it is possible the PO adjusted the carbs to match.

Alternatively, did you remove the carbs when working on the engine for the valve adjustment? If yes... it's possible that something sitting in the bottom of the bowls has been stired up and is now blocking fuel flow. Also double check throttle cables are not overly tight. Make sure everything is seating correctly. Did you inspect the carb boots on the engine? Have you tested for a leak around them? Are the carbs correctly assembled with the factory air box and all hoses plugged up on it or no?

All of these are possible issues with idle and throttle response based upon what little info we have.

Krey

[kharma]

kenny figured this one out.. we had the exact same problem during my carb sync. if you are using the gas tank without the airbox, you need to set the fuel switch on prime (PRI)

[Trackerrrr]

Have Morgan Carbtune attached to all 4 Carbs ~

Did you have the extra vac hole plugged on the fourth carb like Arsenic suggested during your sync? If not then you'll need to re sync.

[jbo197]

My problem ended up being the idle jets were still clogged.
She running now ~

[kharma]

Did you have the extra vac hole plugged on the fourth carb like Arsenic suggested during your sync? If not then you'll need to re sync.

yup, we plugged her good.

[The CyberPoet]

LASunBird
did you sync the carbs after the valve adjustment?
did you tear any of the vacuum port caps when you were reinstalling them after the sync? These tear easily, and you can get replacements from any auto parts store (US sizes, but you can find a thicker option with virtually the same ID on their shelves).
did you check the drain hose for the airbox -- if it's unplugged at either end (i.e. - not attached to the airbox or unplugged at the far end) the bike could do this simply because of the minor vacuum leak induced.
With the engine off, turn the handlebars all the way to the right -- now if you twist the throttle and release, do you hear a loud, clear click as the carb butterflies "snap" closed? If not, it's in the throttle cable adjustments being too tight or routed poorly (or cables binding).


Cheers,
=-= The CyberPoet

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