By jabrams800 on Unrecorded Date: Edit

Recently changed the throttle cable on my Superchief with the Chapperal engine and Mikuni Carb.
I've adjusted the idle speed to the lowest setting possible per the service manual and the darn thing idles dangerously too fast.
Any suggestions PLEASE!!!

jabrams800

By liflod (Liflod) on Unrecorded Date: Edit

Sounds like you have the cable too tight. You should adjust the idle with the cable loosened completely with the adjustment on the top of the carb and use the screw on the side of the carb to adjust the idle. Some carb top cable adjustments will allow you to feel the play in the cable and when you adjust the slack out of the cable leave a little extra play in the cable so you know the idle stop screw is supporting the carb slide an not the throttle cable supporting the carb slide.

By oldnatva on Unrecorded Date: Edit

If the idle stop on the side of the carb is all the way out and the cable is screwed into the top of the carb as far as it will go, make sure the throttle piston in the carburetor throat isn't hung up on something. If that's not the case, you may have a cable that doesn't have enough inner core to give you the adjustment you need. Sometimes you can get enough just by removing the jamb nut on the top where it screws into the carb, and if that doesn't do it, you need to shorten the outer sheath. I've had aftermarket cables that needed to be done, and you can do it with a dremel or die-grinder if you're very careful not to touch the inside core.

Hope this helped
Don

By Jeff Abrams (Jabrams800) (68.59.135.40) on : Edit

Problem fixed and Thanks!
The "Too Tight Cable" idea was it! The adjustment was found up where the throttle attaches to the steering lever. There was a shiney spot where the throttle lever slid down which was our clue to slide it up.
That made the difference and she now idles like a champ!
Thanks again everyone!
jabrams800