So had the NSR at a local race day. Ran it hard for the first two races (didn't do all that well but that wasn't the bikes fault) but with 5 mins to go before the final race, the dam thing wouldnt start.

Got it to run for about 10 secs with a few revs, but it died when I let it go to idle. Gave up on the race and packed up.

Today I removed the tank, drained the carbs, cleaned the plugs and put it back together. Choked it and kicked it over and it ran. Let the choke off down to idle and it died. Repeated the proceedure but no luck at all.

Battery seems fine as servo on turns with the ignition.

Anyone care to give an opinion on what is going on? It has done plenty of running with no setup changes (apart from new head gaskets last week) so I'm perplexed.