hot starting problem

[Julesholling]

My 89 NC30 has just started to refuse to start when the bike is hot. The other day i stalled at some lights about 30 mins into a ride and it just would not start again. Kept turning over and over but not catching. I decided to let the bike cool down a bit and tried again 15 mins later and it started no problem.

Anyone got any ideas what it could be? I've got an MOt coming up next week and am fitting some new spark plugs before it so would like to try sorting it all at the same time.

[mintmansam]

same problem but i think mine is due to it being restricted to 33bhp, try half choke this is what i do with mine when its half way between cold and 90, what temperture you starting it at e.g 70 or less, does it not start when you go for a ride and park up then try and start it about half hour later? , when you press ignition does it start revving slowly then die, then when you try it again does it not rev at all? did it start to lose power as you were riding? i'm not sure if this is the same problem as you were riding for half hour and it cut out

[CRM]

check the tank breather pipe isnt trapped or your having a fuel starvation issue.
same goes for the vacuum pipe, when hot they collapse

[Julesholling]

Thanks for the tips guys. I'll have to check the pipes to see if that's the issue.

The bike runs fine while going and starts from cold ok it's just when it's hot that it won't start again. No amount of choke will help it so looks like it could be something like the pie connections. Off to get the haynes manual to check where the vacuum pipe is now