engine slowed then stalled

[loudzone]

crank it and it starts but after riding it for a few minutes, the engine will slow and eventually stalls.  carb issue or other problems?  thanks

[a_morti]

crank it and it starts but after riding it for a few minutes, the engine will slow and eventually stalls.  carb issue or other problems?  thanks

next time it does it, open the filler cap. If you hear a rush of air, your tank is vacuuming and you have a blocked breather. Compressed air to blow it free. This would be consistent with the bike dying in a run out of fuel manner, so you can coax it on a light throttle before it dies, doesn't just full-stop.

[clarkdw]

Other possibles: Dirty fuel filter or blocked fuel outlet in the tank. Fuel pump not working. Not really very likely in the carbs but very likely a fuel supply problem. If it quits then it is something common to all cylinders which points to the fuel supply for all carbs rather than an individual cylinder which would simply cause rough running as you lose a cylinder. Not much chance of all the carbs getting the same illness at the same time unless it has been parked for a very long time.

Sorry, but gotta ask this one. The fuel petcock is turned on right? 

[loudzone]

thanks.  i will give it a try.