Thanks for the comprehensive answer!!
i had found that it was a 5 speed,I rang Bultaco uk,they are very helpful.
i will try the new points and condenser route before I spend £200 on electronic.
I'm not in a rush and have plenty of time to play with it.
apparently this has not been run for 2 years,although last owner had fitted a new mikuni carb it was all gummed up,that has been well cleaned out so can only be the timing at fault.
thanks again!!