Classic 50 not returning to idle

[BrianVT]

I'm chipping away at trying to get this old girl running right.
When I lift the high idle lever and then put it back down the throttle pivot mechanism doesn't return to low idle. I can push it back that 1/4" or so with my hand with no trouble at the engine. The pivot mechanism all seems to be turning freely. It just seems like it needs a spring to pull it back that last little bit?
I'm also wondering if this has anything to do with the engine wanting to die when I try to go past 1/4 throttle when under way.

 

[racerone]

Find the anchor for the cable on the motor..----Adjust that trunnion / barrel so that it pulls against the idle stop each time.----Do some trouble shooting on the motor.----Compression test is step #1 post your numbers.-

 

[BrianVT]

Thank you. That barrel adjustment makes good sense. Hadn’t thought of that as I assumed it was set prior to me getting it.
I could do compression checks easily on 3 cylinders but not sure I can get to the 4th so I’ve been avoiding that test. I’ll give it a shot.