reminds me of my second RD350
obviously a very different bike and decades apart
but I did a bunch of mods all at once that I'd heard were good
never did get the tuning sorted and it ruined the bike
ran out of oil one day and that provided an opportunity to go back to square one
This is not my first rodeo either, but this symptom was unknown to me so I wanted to ask for help.
Have you seen this? ... particularly the part about whacking open the throttle.
Tjuvstopp etc. - 690 Wiki
I have seen and followed all those procedures as the idle issue is a long term issue that I have not completely resolved. Working on that issue introduced this most recent issue. Most of the time I have to keep revving it at lights to mine and others delight. =)