maybe there is a problem with fuel delivery to the carburetors. it gets enough to start and run a little with choke, then there is no more gas. I will be getting one of these (600R) after a week, and know very little specifics about them (only general knowledge, based on years of Honda), but I noticed it has a vacuum-operated fuel cock (valve). maybe that is defective/dirty/other. can you hook your fuel line to an external tank (or funnel), and make sure the carbs are receiving a reliable supply of fuel?? hope this helps, but your message was November. I hope you got resolved well before now. keep the shiny side up!!