yup tried them they said trial and error! great lots of help, the problem was that you couldnt tickle the carb to start the bike unless the float height was adjusted to just the point of sealing of the float needle so when running the float needle would bounce about on the seat and flood as not quite enough pressure delivered by the floats, on closer inspection it appears the tickle arm that pushes the floats has been screwed onto the tickle knob too far so not enough travel to open the float needle enough to flood for starting, have now unscrewed the knob to the same dimension as my old carb.
Reese Dengler has emailed me to suggest the floats should be level with the sealing face of the float bowl with that setting theres plenty of float lift to shut of the fuel so hopefully now sorted.
this was a brand new CD carb to replace my old worn out one and they do work realy well so dont knock em till you try em though i would kill for the chance to use a mikuni but would have to change class from pre68 to pre74 and i like kicking 4stroke brit bike arse
