Vibrating again help!!!

[Michael11]

Ok so the last post was about a bad bad vibration. It’s a 04 blaster. I thought I fixed the issue. It appeared the counter balance for the crank had come lose. Causing the vibration. I tightened it down and went to ride again. All was good for about 45 seconds and now we’re back to vibrating bad. I’m so lost any help would be amazing

 

[Larry's Shee]

My dollar says that it came loose again

 

[Michael11]

What would cause this to keep happening?

 

[Slydog]

Bad threads.new nuts?
If it already came loose the gear Or shaft and keyway Maybe comprised. If so it will be an ongoing problem.