Flat spot when rolling off then back on the throttle

XsJosh

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Ok so I know there are a ton of carb/flat spot diagnoses posts, I tried searching. Here's my problem. VM 34 rephased, pamco ignition stock mechanical advance. Timing is good, advance seems to work as designed. In 4th or 5th gear around 45-5000 rpms if I roll off the throttle and then back on it has a flat spot or stumble then goes right back to normal. Just curious if anyone has had a similar issue. I'm going out to clean the carbs and check the valve adjustment here shortly. Assuming that doesn't help I'm thinking start with adjusting the needles? Oh and I'll check the plugs as well. Thanks in advance.
 
Sometimes it helps to write things in a post to start yourself in the right direction.
20201011_104940.jpg

Figured I'd find the advance sticking but instead the whole things come apart... I'll start here and let you all know how it goes.
 
So the moral of the story is don't just assume it's the carbs! If you didn't pick up on it the nut had backed off the advancer shaft and the Pamco target was just doing it's own thing. I cleaned everything up and reinstalled with thread locker. Checked the timing and test drove, man what a difference. I hadn't really noticed how crappy it's been running lately.
 
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