I've cleaned a decent amount of carbs over the years, and this has yet to happen.
CB650 carbs. Took bowls apart, jets etc all the usual stuff. Not my first rodeo. Dump the bank of 4 bodies in the ultrasonic for 20 min. Looking spotless, rinsed well everything is looking good. All back together and #4 slide is stuck in the bore (was free before I cleaned them). There's no dirt or gunk, nothing. The carbs look immaculate. I've cleaned carbs this way for years and almost always 100% success. Never had this happen before. There must have been some kind of hot/cold reaction that they didn't like?? How did I clean these suckers and somehow make em worse....
-M