http://www.oldjohnno.id.au/bul.html
A guy working on his old Bultaco at home. Seems to be addressing some similar issues on an engine of similar sophisication Maybe some of his solutions will work for you. Like the $11 programmeable CDI?
2t tuning on other engines
We are not alone !!
We sleep soundly in our beds because rough men stand ready in the night to visit violence on those who would do us harm