Monday morning football coaching....
I totally suspect the tps was the problem. .4 volts is the max. If it goes over, the bike does different things.
Upon deceleration it does NOT turn off the fuel like it should. .399 volts is OK, but .400 is over the top. It will run rich and since it was only .002 over, there were times the motronic would see above or below .4 volts to cause the two different modes
A plugged cat will take away all high speed running. The biggest symptom is backfire through the intake. The next biggest one is a very quiet exhaust note. Glad you got it sorted out. Thank you for reporting back.
Enjoy your bike.