Just in case this will be of some use to somebody one day, I replaced the condenser and that seemed to do the trick - no conking out since. It's consistently mis-firing at around 3000 rpm, but haven't got round to figuring out why yet. Thanks for the suggestions and help - always helps to keep my momentum going - so to speak. PaulyG, I'll take a look at the connections, just in case they could have been a contributing factor.
