Thanks David for the advice and thanks Denis for the offer. Makes me feel a little better to know I'm not the only one struggling with this carby.
I'll experiment a little further with the needles/slides and try your suggestion with the breathing and air jet...hadn't thought of it as being a factor ...

Hi All,

I have recently restored a 1974 TY250A and fitted a Mikuni VM26-8074 round sided carb. From what I have read this seems to be one of the generally accepted replacement carbs.
Unfortunately I'm having a few problems getting the bike to run properly, so I was hoping that someone has had some ...