hi Dave,
thanks for your help on this, iv checked it and its fine.
i did not take the regulator off as it seemed to be working OK because when you turn the engine over it pumps flue and pressure.
the carb is clean and not blocked yet it don't seem to be getting flue into the head?????
iv asked about at my club and got members who know ys engines to look it over and they Can't find why it wont run.

as i said before when you put flue into the head it runs but just burns that bit off. i have got throttle response for that short time and it will rev up so to me the carbs working

i just don't understand why it wont go....... Andrew