I have a gen 1 adv 390 ( 2022) which has done 33k kms . since the last 2 months , whenever I downshift from 2nd to 1st gear ( while the clutch lever is pulled) while coming to a standstill the rpm fluctuates to 4k for couple of seconds and then normalises. This issue first occurred when I started using Quick shifter on the highway.
I have taken this to 2 different service centres ( 1 ktm and another 3rd party) , they have changed the spark plug , done reset of ECU , flashed the latest version, checked o2 señsor , TMAP señsor , clutch cable and clutch plates. all seems to be fine . The service centre ruled out that coz of Quick shifter this issue can happen.
Once these are done the bike performs the way it's supposed to for a day and then back to square one.
Anyone in the group faced this issue and have been able to fix it, please let me know .