Got my 78 back up and running after the winter rebuild. Just can't get the carb tuned. I added a ultima electronic ignition this year but the carb is the unit I ran last year. The carb seems like the return spring is weak or something. I have the idle set screw back way out and the arm that is attached to the cable will not contact the idle screw. So when I adjust the idle set screw in to contact the throttle arm and adjust the jet (1.25 turns out) the idle is way to high. I can " push" with the throttle cable and that will bring it down to a slower idle. So what do you guys think? Bad spring? The spring doesn't look to be broken. I have not put a timing lite on it yet just static timed it based on the instructions provided with the ultima. Any input would be appreciated.

Thanks
T-Ron

 

It is unlikely the Ultima is part of the problem. When i static timed it on my '78 the timing came out to be 38`; i think most guys run at that setting. I set mine back to 35` to help eliminate pinging.

The areas to consider are the throttle cable adjustment, the throttle plate in the carb, and the carb itself.

Did you have the cable off the bike? Did you dismantle etc the carb?

 

"The areas to consider are the throttle cable adjustment, the throttle plate in the carb, and the carb itself"


+1

may even be a lack of lube or some gumm from last years fuel

 

If you did remove the throttle plate before, then I suggest you loosen the two throttle plate screws and shut the butterfly letting it seat fully in the carb's bore.
Then hold it seated while you tighten up the screws.

From your description it sounds like you do not have the plate seated. The plate needs to close fully and if it is just a tad off it will result in a very fast idle speed.
pg