If it dies when you open the throttle quickly, that is indicative of it being a big, long stroke single. At low engine speeds a quick blip of the throttle will drastically change engine vacuum, but there isn't enough air velocity through the carb for the carb to work. Gas won't be picked up through the jets so it runs lean and stalls. Learning to roll the throttle on will eliminate most of this. This feature is why car carbs had an accelerator pump to pump in more fuel at low engine speed/large throttle openings. You can tune some of it out, but eliminating it requires an accelerator pump or jetting it so rich that you almost instantly foul plugs. When properly jetted you will never notice this issue with proper throttle technique.
A larger carb will make things worse if we are speaking of the engine dieing with quick blips of the throttle.That's one reason small carburetors are often put on street bikes where fussy engines aren't tolerated by the owners.
Advanced the timing and it runs better. Drove it up and down the street and it had decent power and throttle response. Still needs some tuning though. Runs rougher than I'd like.https://www.youtube.com/watch?v=FcRd6lkCCt8&feature=youtube_gdata_playerHow do I more precisely set the timing? I'm lost without timing marks.