Originally Posted by
HillRider
I think you have too much clearance between the "finger" of the chain watcher and the inner face of the chainring. Set up properly the chain should not be able to move past the teeth of the chainring. Shift into the granny and the big cog and adjust the finger to just barely clear the chain's side plates. Also be sure the chain watcher is set high enough to guide the chain onto the granny ring.
On the bike with the Third Eye Watcher, I do have it installed as described. The chain never drops to the BB shell where the external bearing is installed. Because the inside plate on the derailleur is designed for a 30t chainring, the chain disengages from the chainring and just sits on the chain retainer when I upshift. The good news is that I can get it back on the 50t outer chainring by just gently pedaling and upshifting. It's not ideal, but I don't lose pace and I stay on the bike.
I have not used the K Edge item yet.