Same thing for me....
I have three 135's and one 155...and can't set the bell reliably on any.
Edge and bow are fine but bell will only sound about 50% of the time, the other 50% triggers the edge. I've been using my ride as dual zone. I give the edge the bell sound and then all strikes on the bell fire as a bell sound, and it's super playable too...Still would be nice to have all 3 zones though.
I'm not home to post my settings but I set it up using midi-ox like this
I set my bow threshold to around 30
I increased the edge threshold until I got reliable aftertough messages. Think it was around 48-54..
Then adjusted bthreshold for the bell. Around the 18-22 mark.
No joy...and I must have had those thresholds in every permutation you could think of!!