thank you everyone
here are some more observations:
1. there is a saucer-shaped thing running from a back plate in the engine block to the inlet manifold. ive been told this reburns crap
on the saucer shaped thing, there is a tiny hole (supposed to be there). when you put your finger over it, the engine sounds like its going to choke and die
you can see it in the right hand corner at
http://www.angelfire.com/mech/ducho/engine_bay.JPG (cut n paste link)
tube running behind rocker cover, under blue tube, then the saucer and it goes down behind the engine
2. i took the air filter out and it seemed to run louder and rougher (perhaps even more confidently), but the problem still occurred when run without the air filter.
3. i filled up with BP ultimate on saturday. changed the oil (not the filter) sunday. problem started sunday night.
problem continued monday after plug change.
i dont think i have a fuel filter
4. ive been told you need to know what youre doing for a points gap check. Three people have agreed it might be the points gap thingy
i will do everything i can (carby clean out, points clean, breather valve saucer thingy clean)
i really want to make it to sunday eastern creek, maybe makka ill see you if the problem cant be fixed thanks
thank you everybody i appreciate it all