OP

Quoted from schudel5:

So I'm looking into an issue with a Champion Pub for someone, and I'm stumped. It's not my game so I'm not sure exactly the start-up sequence the jump rope does at boot up, but I can describe what it's doing and what I've done.
When the game is turned on and the boot up sequence is finished, the jump rope turns clockwise at a steady pace maybe one revolution. When it gets to the 12 o'clock position it speeds up until the 6 o'clock position and then goes at a slow pace until it reaches the 8 o'clock position and stops. I believe this is the normal behavior, but I'm not sure.
Now, about every 5th time the game is turned on it does the above rotation, but when it hits the 6 o'clock position instead of slowing down and stopping it speeds up to a fast rotation and never stops.
Now I found this thread from 4 years ago https://pinside.com/pinball/forum/topic/champion-pub-jump-rope-problem and I've done everything in the thread. I disassembled the jump rope and speed bag assemblies. Checked foam pads and insulation, checked optos and motor EMI board. Everything is good. I replaced the security chip and even the uln2803a at u20. No change.
Not sure what else to do or check. Any ideas?